Tuesday, December 4, 2012

December musings: edibles--You Can Grow That!


The off-season edibles.

Sitting in my kitchen the day after Thanksgiving, cracking pecans I had picked up that morning and roasted, drinking pomegranate juice somebody had squeezed from a mere fraction of our crop, and eating a last ripe, red sweet pepper from the vegetable garden, I thought about heading out to see if the Satsuma mandarins were getting sweet enough. Some of the Robert Livermore walnuts were mixed in with the pecans.
Earlier I'd told the workers at the nut processing plant next door, who like to take a walk for their break each afternoon and who often enjoy our garden, to go ahead and help themselves to some of the Fuyu persimmons. I don't really have a use for 300+ fruit this year, and that is a light
crop. Their husbands like to harvest the prickly pear cactus fruit: I've watched as they stand along the county road, carefully digging the thorns out with their pocketknives before they eat the fruit on the spot. Sometimes the tender new growth disappears for nopales.

Looking out the window at my meadow of fine fescue, I thought to myself, this Sacramento Valley of Northern California is sure a nice place to garden. We get enough chilling for the deciduous ftuit and nut trees, but we aren't so cold that (most) citrus are harmed. And the number of plants on my property that just take care of themselves and produce food for casual picking and eating always amazes visitors. I'm not talking about the vegetable garden, or the actual orchard. Just things I've planted in various places that I put almost no effort into.

Ripe kumquats
are on my tree year-around, and the tree is right along the rose garden path for easy picking.

Pineapple guavas
in abundance every October.

Quince
. Hmm. They smell great in the fall, and I have friends who use them.

Walnuts
and pecans in fall, sitting on our kitchen counter through the winter.

Persimmons
: Fuyu from November, Hachiya from December, until the birds finish them off.

Pomegranates
in November and December. Finally found a way to juice them this year!

Satsuma mandarins
are anticipated by extended family and friends for the holidays, and through January.

Navel oranges
ripen from February to April.

Strawberries
in early spring, Boysenberries and their cousins in late spring. I really should get the caneberries under control, but they do make great bird habitat.

Midsummer we enjoy the Persian mulberries
until the birds take over the harvest.

Almonds
in late summer.

Family, friends, and strangers expect to harvest from the fig
trees that have been on our property for decades.

What's interesting is that these zero-input food plants mostly provide food in the 'off' months. Mid-summer my regular orchard trees – peaches, plums and pluots, and all the other prune-me water-me crowd – are abundant. And the vegetable garden is overflowing. But just as all that is winding down, as I've enjoyed that last worm-free apples (a tiny percentage of the crop, sad to say) and the sauces and salsas are made, it's those fall nuts, winter citrus, and spring berries that fill the gap.

What care do these all get? I water them. Some as little as once a month. Fertilizer? Nope. I could prune them for size control, but mostly I don't bother. Birds enjoy the surplus that's out of reach. I'm fortunate to have unlimited space, but most of these could
be kept small in a regular back yard. Pecans and walnuts are very large trees, perhaps not suitable for your situation. Persimmons will get plenty big if you let them (my Fuyu is at least thirty feet tall), but can be kept lower. Consider fruit litter when you plant them. If you don't eat it, the fruit may end up on the ground.

There's a lot I could add, and probably will. Meyer lemon, Chilean guava? I'm sure I'll find places for those, too. If it's edible and there's a path, there's probably a place for it. I have an Arbutus unedo
(Strawberry tree) that people like to sample now and then. Jujube fruit mostly falls to the ground; I really need a dehydrator! If I gave my asparagus bed, now over two decades old, more attention it might yield more. As it is I get a sampling of shoots in early spring, and enjoy the beautiful ferny foliage in summer. Maybe some day I'll even harvest some of my bamboo shoots.







Kumquats


Quince


Pecans

Mandarins

More pictures at our website here: http://redwoodbarn.com/Decmusingsedibles.html

Tuesday, November 27, 2012

I've linked a number of my articles about water conservation on one page here: http://redwoodbarn.com/waterconservation.html

Sunday, November 4, 2012

Great Natives for Valley Gardens




    Low Water Plants continued:

    Great Natives for Valley
    Gardens




    written for the Davis Enterprise, November 01 2012
    This is part of a continuing series of articles on plants that can grow and look good with low water. The focus here is on low to medium shrubs for very limited irrigation, especially natives. Low-water taller shrubs were discussed in our November 2011 article.

    Note that some California native plants require drought, as compared to tolerating drought. They'll die if you water them too often. In garden references you'll sometimes see the notation "needs good drainage" or "short-lived." Those are code for "susceptible to crown rot," meaning that if they get watered too frequently in warm weather they may get attacked by Phytophthora, a fungus-like organism that invades the plant at the crown and kills it swiftly. Many, but not all, of our native plants are vulnerable.
    Watering deeply and infrequently, and avoiding mulch around the stem, are the best practices for avoiding crown rot.

    Low and ground-cover shrubs

    Botanical name: Arctostaphylos species
    Common name: Manzanita
    As a group I am leery of manzanitas because they are so easy to kill, being very sensitive to overwatering. But a couple of garden cultivars are less vulnerable. Howard McMinn grows to about three feet tall, four feet wide or more. It has a dense growth habit, with shiny green leaves that contrast nicely against the red stems.
    Baccharis pilularis Twin Peaks
    Dwarf coyote brush.
    Very tough, drought-tolerant native. Great for attracting beneficial insects. Otherwise a dull, somewhat scruffy looking plant. Unbelievably resilient, so it earns its place on my list on that account. Nobody's going to say, "ooh, look at your coyote brush!" But you don't ever have to prune or even water it.
    Ribes viburnifolium
    Catalina perfume
    Will grow in considerable shade, spreads steadily to make an attractive ground cover. Fragrant evergeen foliage. Light pink flowers in late winter attract hummingbirds; small red berries attract songbirds.

    Salvias: sages.



    Salvia splendens
    Red Hot Sally
    For many years, the annual Scarlet sage was the best-known member of Salvia. These showy flowers are planted in spring, bloom through fall, and then die with frost. But the blooms are non-stop and they attract hummingbirds as readily as their perennial and shrubby cousins.
    Salvia Pink Frills
    Patrick Worley, the breeder at Suncrest Nurseries who introduced this describes it as a "greggii type" to about 2 feet tall and wide. These lighter colors stand out nicely against the dark green foliage. A plant will have 30- 50 flowers at a time during autumn.
    Salvia Dancing Shadows
    The breeder describes these as "painted icy pink and white flowers" on red-violet stems. Another profuse bloomer in the sun-loving, drought-tolerant Salvia greggii group.
    Salvia Golden Girl
    Yellow is the holy grail of Salvia breeders, and this is the closest yet. Suncrest Nurseries describes it as "very compact" to 18 inches, which makes it a low-grower in this group.
    fine fescueCarpenteria californica
    Shown here in May, the native Bush anemone gives several weeks of bloom in late spring. It is actually a rare species, growing only in a few sites in Fresno and Madera counties. But growers of native plants have popularized it for California gardens. Unlike many natives, it is not fussy about soil and can tolerate regular watering, but is also tolerant of drought.
    Mahonia aquifolium
    Oregon grape
    Ok, it's not native here, but it is native over on the northwest coast. Mahonia has bright yellow flowers in winter, edible fruit that attracts songbirds, and tolerates drought or watering, sun or shade. Prickly leaves resemble holly. This original species is tall and rangy, but new forms have more compact growth habit, shinier leaves, coppery new growth, and more abundant bloom.
    Botanists recognize hundreds of species in the genus Salvia, possibly up to a thousand. While most gardeners knowSalvia officinalis (garden sage, from Europe) used in cooking, more than half of the species are from South and Central America, with a few species from California and the Southwest. Some types are frost tender and prefer regular watering. A few like some shade. But our native species and their hybrids are generally very tolerant of drought and hot sun.
    The flowers of Salvias are fascinating up close. They are "bilabiate" which means "having two lips." There are often glandular hairs on the flowers and leaves. The stamens are fused into a lever, which bends down and deposits the pollen on the back of the visiting bee or bird as it probes the long flower tube. The female flower stigma develops next and is bent down to receive the pollen. The flower is adapted to many pollinators, rather than any specialized one. Salvias are always active with wildlife. Hummingbirds, butterflies, carpenter bees, and bumblebees are attracted to the flowers. Beneficial insects harbor on the foliage. Songbirds like the small seeds. A mixed planting of salvias, lavenders, rosemary, and daisies will give year-around color, help prevent garden pests, enhance pollination, and require very little water once established.
    Southwestern native sages
    Salvia greggii, S. microphylla, and more. These are the stars of the autumn garden, at their peak of bloom right now.
    For gardeners, this is one plant group where there has been a sea change in availability of species, hybrids, and cultivars in the last couple of decades. My 1970 edition of the Sunset Western Garden Book lists ten species on about half a page, with only three cultivars. Native plant specialists carried a couple of species. In the herb section of your local garden center you could find common garden sage for use in your holiday turkey stuffing. Annual Scarlet sage was a popular summer bedding plant. That was about the extent of the Salvia trade.
    Then in the early 1990's Salvia greggii, now called Autumn sage, started to show up. No named varieties, but it caught on quickly for the bright pink late summer and fall blooms. Now Salvias cover six pages in the new 2012 edition of Sunset. One grower has 30 to 40 varieties available.
    What makes these important for Valley gardeners is that many of them come from hot, low-rainfall regions. Salvia greggii is native to the high deserts of southwest Texas and Mexico. Salvia microphylla, Graham's sage, comes from Southeastern Arizona and Mexico (it is recognizable by the much more fragrant foliage, which occurs in some of its progeny). When you bring these two together in a garden, they hybridize very readily and reseed happily. So now there are dozens of natural and intentional hybrids, in an ever-increasing range of colors.
    For taxonomy buffs: the naturally occurring, original hybrids between S. greggii and S. microphylla and other species were given the name Salvia x jamensis. The 'x' indicates an inter-specific hybrid of known parentage. But that was a while ago. The exact parentage of many of the new cultivars is simply unknown at this point, so they often just have a cultivar name; e.g., Salvia 'Dark Dancer'. The genus name (Salvia) is properly italicized; the cultivar name should be in single quote marks. Neither is standard editorial practice in the news industry, but it is how you will usually see the name in journals and reference books.
    Hybrids and cultivars in this complex group are generally 2 to 4 feet tall and wide. Most branch heavily from the base. S. greggii types tend to get woodier and taller, eventually a little rangy. You can cut these back in spring to keep them shorter and more compact. The bloom is light and steady in spring and summer, and absolutely profuse in fall.
    The color range started in reds and pinks, then broadened to lavenders and purples. A light yellow form appeared; now there are some stronger yellow ones.
    Every time I think I have a favorite, another variety comes along. In addition to those shown here, I have created a pinterest board of my Salvia pictures: http://pinterest.com/redwoodbarn/salvias/
    California native sages.
    Mostly spring-blooming, these have denser growth habits than the previous species and tend to get larger.
    Salvia apiana 
    Silvery-white leaves give this the common name of White sage. Three feet tall and wide; white flowers, intensely fragrant foliage. Hardy to 20 degrees F or lower. This is the one used for burning in purification rituals. Hard to propagate and thus not common in the trade. It is easy to kill by overwatering.
    Salvia clevelandii 
    Cleveland sage is a Southern California native that grows to about three feet tall and a little wider. It has attractive grey-green foliage, and tall whorls of blue flowers in late spring. A very useful shrub in low-water landscapes, it combines well with non-native low-water plants such as Cistus (rockrose), lavenders, and rosemary, as well as natives such as Ceanothus (wild lilac) and manzanita. A few cultivars: Allen Chickering has lavender-blue flowers; Winnifred Gilman's are darker blue.
    I have found this plant often harboring ladybugs in the adult and larva forms in winter and early spring.

    A few other native shrubs



    Romneya coulteri
    Can you see why it's called Fried-egg flower? Matilija poppy is the other common name of this Southern California native. A big (up to 8 feet tall!), spreading, somewhat coarse-looking plant with flowers that bob above the foliage in summer. Easy, tough, moderately invasive, tolerant of watering or drought.
    Carpenteria californica
    Bush anemone
    This slow-growing, tidy shrub to four to five feet, from our coastal mountain range, has shiny leaves and a compact growth habit. White showy flowers in late spring resemble anemones. Tolerant of sun or light shade.
    Ceanothus species and varieties
    Wild lilac
    Attractive shiny leaves and fragrant blue flowers in spring. Water deeply and very infrequently in summer; they are notorious for dying abruptly in warm weather when they get watered too often. There are low spreading types. Centennial stays under a foot tall and spreads several feet. Yankee Point grows to two to three feet tall and spread six to eight feet or more.
    The UC Davis Arboretum touts Valley Violet, a well-mannered low shrub with small leaves and unusual lavender-pink flowers.
    Several varieties grow to six feet or so, some spreading wider. Julia Phelps has dark, small leaves and vivid cobalt-blue flowers; one of the showiest in bloom.
    Ray Hartman, mentioned in the Nov. 11 article, is big, fast, and upright, tall enough to train as a screen or small tree to fifteen to twenty feet.
    Mahonia aquifolium
    Oregon grape
    Native to the coast side of the coastal mountain range. Shiny leaves, bright yellow flowers in winter, blue berries that attract songbirds. Tolerant of sun but better-looking in some shade and tolerant of deep shade. Compacta is a denser, shorter variety. John Muir and Ken Hartman (a hybrid) are selections with denser foliage, spinier leaves.
    As you change over your landscape for lower water use, consider some of these plants native to California and the southwest for their durability and beauty!
    Previous columns about low-water plant choices in the Davis Enterprise columns here.
    Look for the October and November 2011, January 2012 and June 2012 columns.

    More pictures of Salvias here
    and on Pinterest here.c 2012 Redwood Barn Nursery
    www.redwoodbarn.com

Friday, October 5, 2012

Pistache for posterity

A 94-year-old lady came in today and bought our largest Chinese pistache to plant in her front yard.
 I was raised that you don’t mention a lady’s age. But she volunteered it, and I think at a certain point that old rule doesn’t apply.
I’ve known her for a long time. She isn’t getting around as well as she used to, so her sister drove her in. Her sister lives in Texas, but comes out to visit and help out now and then. She’s 91.
 The old walnut tree in their front yard died, so it had to be taken out.
 “We weren’t going to replace it,” said the sister. “At our age, we’d never see it grow. But,” she paused.
“You should plant trees no matter what your age,” I replied.
“Yes, you should,” she agreed firmly. “Plus, our doctor lives across the street, and he said he wanted us to plant a tree.”
“You do what your doctor tells you,” said the older sister with a smile.
So, doctor’s orders, she bought the largest tree we had and arranged for a young man to come out and plant it.


 The city had planted one Chinese pistache already in their front yard a while back when the Modesto ash came out. That one is a female tree, doesn’t color up so well. “The females do have pretty berries,” I said. “And the songbirds enjoy them, even if they are a bit of a mess.” But they especially wanted the fall color. 

The reason we sell the grafted Keith Davey Chinese pistache is for that reliable fall color and the fact that it doesn’t have the berries. Most people prefer that; they want to know they’ll get that familiar bright red color. And while the pistache berries aren’t squishy, there sure can be a lot of them. Pistacia chinensis is dioecious, having separate male and female trees. With nursery stock grown from seed, you have a 50-50 chance. And the fall color ranges from yellow to orange to purplish to red.

I’m partial to all of them. I live along the freeway, where CalTrans has planted mixed seedlings. And Chinese pistache is fecund enough that more seedlings have augmented that stand. I bought a tray of seedlings from a grower years ago, culled out those that lacked good fall color, and planted half a dozen of the best on my property. I have some male and some female. Lots of winter songbirds enjoy the female trees. But I understand why homeowners want to know what they’re getting. For reliable fall color, plant Keith Davey.
Chinese pistache is one of our most common landscape trees. It can tolerate drought (many of the trees on or adjacent to my property get zero summer irrigation). It can also tolerate reasonable lawn watering. No pests and few diseases. A small percentage of trees in some parts of town die from a vascular disease that looks and spreads like verticillium wilt. The pathogen hasn’t been confirmed, but if you do lose one I suggest avoiding trees that are known to be susceptible to that when you replace it. But thousands of them grow without incident around the Sacramento Valley.

 The growth rate is what we call moderate. Watered deeply, fertilized a bit when young, they grow two to three feet a year up and out. In ten years you have a nice medium tree with equal spread to height. In a couple of decades, you have a good-sized tree. Eventually they can get quite large. Roots are deep. A little gawky when young, they barely require pruning once established.

This is the tree that has the most reliable, consistent fall color in our area, beginning in late October and continuing through November. When they turn color varies with watering regimen, exposure to cold, soil nutrition, and other factors. Unirrigated trees, such as those along the highways, turn color first. And even with the right genetic material, some trees don’t give good color some years. A tree in a sheltered courtyard may disappoint you, and some years are better than others. Nature is fickle.

 But if you want fall color, this species is your best choice here. And in the right year, the right place, the right tree, the results are spectacular.

 I like their attitude. Yep, they can grow that. And you can too.

Saturday, August 4, 2012

Rethinking Lawns

Lower Water Lawn Options

written for the Davis Enterprise, July 26 2012

As Davis faces water rate increases, garden professionals get lots of questions about ways to conserve water in new and existing landscapes. Previous columns have discussed low-water options for shrubs, ground covers, and trees in the landscape. The biggest water-user of all is the lawn. But that presents a conundrum, because the lawn is part of the yard we really use. Someone moving to a new house was asking about options and noted, “I have a big conflict about water usage. But we have two small kids who play on grass. Tough to play on cacti beds!”

Let’s not disparage lawns too much. That water use does provide natural air conditioning, heat reduction, and reduces dust. A normal lawn watered optimally requires about a thousand gallons of water a week per thousand square feet. But it takes that water and pumps it back up into the air around your yard, providing evaporative cooling. Grass is much cooler to walk on and work around than are bark, decomposed granite, concrete, and other non-plant surfaces. In California we use our yards as extensions of our living areas, and there is no question that a lawn is a more comfortable place to be than a drier landscape. Dogs and kids like to play on them.

As noted in my October column: "Form follows function," Louis Sullivan said. Let your landscape form follow the actual use patterns of your family. Lawns are for kids and dogs, and are usually unneeded in front. Put lawn where you will use it, not just where you'll look at it. Reducing your total lawn area is a simple way to save water.

You can probably reduce your total water usage on your existing lawn. Lawns don’t need daily water. A rule of thumb for traditional lawns is one inch of water, two times a week. Measure to see how long your sprinkler takes to put out an inch of water. I find most people aren’t watering long enough, but are watering way too often.

You could get a “smart timer.” Once the realm of commercial turf areas such as golf courses, these have become less expensive and may be appropriate for those of you with large lawns.

These amazing lawn sprinkler timers communicate with local weather data sites to determine the rate of watering needed, and adjust accordingly. When weather is cooler than average, they reduce the output. You can do the same thing, of course, but it takes some awareness of actual water use rates. The IPM web site maintained by UC Davis has links to weather stations all over the state, providing ET data (ET = evapotranspiration, the rate at which plants use water. It is measured in inches, just as rainfall is. Lawns use up to two inches of water a week in our hot, dry climate).

Go to http://ipm.ucdavis.edu/WEATHER/index.html and find the local weather station. Add up the ET rates and provide the water use calculated for the previous week.

Or you can be intuitive: if it’s cooler than average for the time of year, cut how long your sprinklers run a bit. We tend to fluctuate between short intervals of high temperatures, and periods when the delta breeze prevails and cools us off.

Keep an eye on your lawn. If it is looking duller green than usual, it is probably water stressed. Poke a trowel into the soil and assess the moisture. Water rates we give are optimal. Perhaps we can all learn to accept a little turf stress as long as the overall appearance is good enough.

If that all seems too complicated, the smart timers may be worth the investment. Local irrigation supply companies can give you more details, and a landscape contractor can install one for you.

Second option is to change your type of grass. All grasses are not equal in their water use. Until the advent of tall and dwarf fescues, most lawns were blends of bluegrass and perennial ryegrass. Those are the highest water users, and tend to be more susceptible to diseases. If you’re in an older neighborhood, it is possible you still have a blue/rye blend.

The newer, coarser-bladed fescues (tall and dwarf) can get by with as little as 20% less water than those older grasses. They are deeper-rooted, so they can go longer intervals between waterings.

If you have an older lawn, simply converting your lawn to a tall or dwarf fescue would enable you to cut your water use immediately. But they have a less refined look and require taller mowing height (preferably about 3 inches height in summer). If you are in a neighborhood built from the early 1990’s on, your lawn is probably already one of these blends of “dwarf tall fescue.” Yes, I know it’s an oxymoron: “dwarf fescues” are the lower, slower-growing strains of tall fescue.

Fescue is an important group of grasses. Most lawn blends that are labeled for shade contain another type: the fine fescues. The two most common are creeping red fescue and chewings fescues. They happen to tolerate more shade than other grasses, including the dwarf and tall fescue cousins. But we should all be using these more, as they are tolerant of even less water. Data I have seen show fine fescues can use up to 20% less water than the dwarf/tall fescues. They grow in full sun just as well as in shade, and make a very attractive lawn. As with other fescues, it is very important to mow them high (the grass, not you). Fescues have a high growing point. If you cut them too short, especially in hot weather, a lot of the individual plants will die out and the lawn may thin out. Mow at three inches if possible.

So converting your existing lawn to fine fescue can enable you to use 20 to 40% less water overall. If you don’t mind the appearance of grasses of differing texture, you can just over-seed your lawn and let the fine fescues fill in around your present grass mix. Otherwise, you can kill your lawn with chemicals or black plastic first. Fall is an excellent time to do the seeding, and it’s a pretty simple operation.

1. Mow your lawn as short as possible.

2. Rent a dethatcher and run it over the lawn. This machine rips out old, dead stems and leaves, exposing bare soil between the remaining healthy grass plants.

3. Apply a starter fertilizer.

4. Seed the fine fescue grass at 1 lb. seed per 100 square feet.

5. Top-dress the lawn with a fine layer of bagged compost.

6. Water daily, one or two times each day, until the grass germinates and grows to an inch or two of height.

7. Gradually reduce watering. Once you’ve mowed once or twice, you can revert to your regular watering schedule.

Timing this whole project just before a rainstorm in October or early November virtually guarantees success.

A final option is to consider a meadow. These fine fescues make very attractive groundcovers when left unmowed. On my rural property I have a large area where I seeded chewings fescue, hard fescue (a pasture grass), and creeping red fescue. I water as little as every two weeks in the summer. We allow it to grow long for an informal look. Once a year, in the spring, my strapping son rents a high-wheel mower from JB’s Power Equipment and mows the whole thing to prevent flowering and to manage any weeds that might be trying to poke through the grass.

It’s a great area for throwing balls for our dogs, and kids of all ages love to lie on the soft green grass. It’s very active with wildlife: last year when he mowed it praying mantids were scattering in all directions. Swallows fly above the field each evening. Unmowed grasses are important harboring sites for beneficial insects.

The UC Davis Arboretum is establishing a large area of California native grass in a meadow at the edge of the lawn area near the oak grove on the west end. They’re using Blue grama (Bouteloua gracilis). Other options include native strains of Festuca californica and Festuca rubra (there are those fescues again). These are available as small plant starters through Suncrest Nurseries, a wholesale grower in the Bay Area. And many larger ornamental and native grasses can be used for informal meadows. The key is to plant a mowable, walkable, lower-growing species where you’d be walking on it, and then plant some of the taller ornamental grasses on the edges.

We need to rethink lawns. Not necessarily get rid of them, but put them where we use them. Create the effect we want with lower-water grasses. And develop a new culture: less clipped, less formal, more appropriate, more sustainable, and less expensive.

You can find previous columns about low-water plant choices in the Enterprise archives. Look for the October and November 2011, and January 2012 columns. They are also available at http://redwoodbarn.com.

A work in progress: the UC Davis Arboretum is converting a large part of the lawn at the west end to native grasses. Please don’t walk on it while it’s establishing! This species should be able to grow and look good with much less frequent watering than traditional turf.

Our meadow of fine fescues. This area was seeded with chewings, hard, and creeping red fescues. The first two form clumps, the latter spreads. The effect is informal, great for playing with dogs and kids.

Here creeping red fescue has been seeded pure in a shaded area and allowed to grow without mowing, making a soft ground cover. Creeping red fescue is more tolerant of shade than most other lawn grasses.

fine fescue

The leaf blades of the fine fescues. The individual blades are rounder and much narrower than other grass species. You may already have these grasses in your lawn, as they are often added to seed blends for their shade tolerance.

Many ornamental grasses can be planted, preferably in groups or masses, on the edges of lawn areas to continue the visual effect. Most are much more drought tolerant than traditional turf species. Here is a specimen of Nassella tenuissima (formerly Stipa tenuissima), a fine-leaved ornamental grass.

c 2012 Redwood Barn Nursery

www.redwoodbarn.com

Saturday, July 7, 2012

Garden Questions in Early Summer!

I heard the “climate zones” have changed because things are getting hotter. Which zone are we in now?
Recently the USDA Plant Hardiness Zones were changed to reflect the warmer winters that have been observed in many parts of the country. No changes were made to California zones, because winter temperatures have not warmed in most parts of our state. The major changes have been observed in the southeastern U.S.
Western gardeners generally use Sunset Zones, not USDA zones. USDA zones only reflect winter low temperatures. Sunset Zones, created by the publishers of the Sunset Western Garden Book years ago, are much more detailed, showing the differences caused by local geography. Davis is in Sunset Zone 14: a hot interior climate with strong coastal influence (the delta breeze that we all appreciate so much on summer evenings). Woodland is in Sunset Zone 8: less coastal influence. For winter hardiness purposes, both are in USDA Zone 9.
So a recent comment in a gardening article in the Sacramento Bee got me curious. From the June 12 edition, in an article titled Gardening's Busy Season Starts With Understanding Climate, an author from the Bay Area is quoted, "Our weather is changing. I've lived in Alameda my whole life, and it's not the same climate I grew up with - it's hotter. We have to adapt. It's one more challenge for gardeners."
Well, the statistics don't actually show that for many parts of California, and particularly not for coastal areas such as Alameda. 30-year temperature data compiled by the National Climate Data Center shows average temperatures have dropped in California's coastal cities and areas such as Davis and Sacramento that have strong coastal influence, while temperatures have increased slightly in interior cities such as Fresno and Redding that don't have the delta breeze. Reasons? Perhaps the Pacific Decadal Oscillation, of which we are in a cool phase.
Bottom line: California gardeners needn't worry about reports of gardening zones changing. Your old books are still valid.

Question from another plant pro: Thrips on roses. What is your experience and what would you recommend to a homeowner to manage the situation? They used the Bayer 3 in 1 product 10 days ago.
Thrips are tiny insects that feed on the tips of the rose buds before they open, causing the petals to distort and the flowers to open imperfectly. Pull back the petals and you will see fast-moving very skinny insects less than a quarter-inch long inside the bloom. Thrips in our area show up on flowers as the nearby grasses dry off in late spring and they move into our gardens looking for food; they are worse on light-colored roses than dark ones.
Spraying with anything is likely to delay the population increase of the natural predators. It isn't the answer the gardener wants, but it's the honest one. We all need to stop selling and using the combination products due to their environmental harm and unintended consequences.
Bayer 3 in 1 is a combination insecticide, miticide, and fungicide. The insecticide part is taken up into the plant and poisons the insect after it feeds. Since it has to feed first, and the feeding is what causes the damage, you still get the damage. It is one of the very worst combinations a gardener can apply with respect to harming bees. Combine tau-fluvalinate with tebucanazole and imidacloprid? Toxicity of the first ingredient to bees increases something like 1000-fold when combined with SBI fungicides such as tebucanazole. And the imidacloprid itself is known to be harmful to bees. So we have a gardener unnecessarily applying a miticide and a fungicide to a plant on which the only identified pest is an insect, and doing significant harm to bees and other beneficial insects with a product that will only marginally manage the thrips (if at all).
Neem sprays might help, since they could smother existing thrips and repel any new ones. Vigorous washing of the plant might help, and will reduce aphids and mites in any case. Ace hardware stores sell a hose-end pressure washer that is great for managing pests on garden plants. More to the point, thrips season will pass. Beneficial insects populations will catch up with the thrips, hot weather will reduce the reproductive rate of the pest, and your roses will be back to normal again.
Bottom line: there is no conventional pesticide, labeled for thrips or not, that gives good control on roses. The damage is done to the blossom before the pesticide takes effect, even if it works. Thrips populations develop resistance to pesticides very quickly. Some products have very adverse effects on beneficial insects. I know garden center professionals want to sell a solution to a problem, but often I find myself explaining that we don't have one. These problems tend to be seasonal and of short duration.

A dwarf Butterfly bush? Wowzer!
We appreciate your enthusiasm. Yes, breeders have achieved short, compact-growing Buddleias. Commonly called Butterfly bush, Buddleias have been long-time garden favorites for their long season of bloom, fragrance, attraction to hummingbirds as well as butterflies, and tolerance of heat and drought. But even the most compact types got to 5 to 6 feet tall, and the older ones were even taller and rangier.
Enter the Buzz Buddleias, and the Flutterbye Petite Buddleias. Little three-foot mounds of color, blooming non-stop from May through summer. Available in purple, lavender, pink, and white, these can be kept in containers or planted in the front of the border. Mix them with lavender, rosemary, rockrose, or other sun-loving low shrubs and perennials.

My clematis came up and bloomed real nicely, and now it's set those seed things. How can I get it to bloom again? Do I have to cut those off?
That plant won't bloom again this season. Each clematis variety blooms for a few weeks. But there are varieties available for bloom at different times spring through mid-summer. The seedheads are interesting and sort of attractive; removing them is tedious, unnecessary, and won't yield any further bloom.
Clematis have a reputation for being fussy. They're not, really; they just like their roots in rich, loose soil that is shaded a bit, and they need regular watering. The tops are fine in full sun or partial shade. Once established, they can be very long-lived and carefree.
Most types put on vigorous growth in just a few weeks in the spring, then bloom, and then rest for the remainder of the season. So the key is to keep the root system healthy and vigorous to build up the plant for the next growing season. Fertilizing in late summer with an organic plant food will help make a more robust plant the following year.

I bought some moss ground cover and planted it in the shade, and it isn't doing well. Looks like it's dying. Is it not getting enough water?
Wrong plant, wrong place. Or if you prefer: misleading common name. Irish moss and Scottish moss (varieties of Sagina subulata) are actually not mosses at all. They are in the carnation family and prefer full sun and slightly dry conditions. For a soft green look in moist shade, try Baby's tears (Helxine soleirolii).

My tree in my lawn has never grown as well as the others. Should I feed it? Why do you recommend keeping grass clear away from trees?
Grass roots compete significantly with tree roots! Trees planted with grass growing up to their trunks grow as much as 30% more slowly than those with the grass cleared. Feeding trees in the lawn is very difficult because grass roots are very efficient at 'stealing' nitrogen. You end up feeding the grass, not the tree. Clear the grass from an area at least 3 to 4 foot diameter around each tree. Then you can fertilize a young tree, using an organic source of nitrogen in spring and/or fall. Established trees need no feeding unless they show specific deficiency symptoms.
Trees in grass are also vulnerable to damage from power equipment such as mowers and especially weed trimmers. Repeated damage harms the water and food conducting part of the tree (the cambium) and stunts it, and creates an avenue for disease to enter. Finally, grass or mulch up against the stem of any plant traps moisture, inviting crown rot fungus. Trees and grass don't mix!

For further reading:
To check out the new hardiness zone map, visit http://planthardiness.ars.usda.gov/PHZMWeb/

Want to see the differences from 1990 to 2006? For an interactive map, visit: http://www.arborday.org/media/mapchanges.cfm

Article about climate data: http://www.sacbee.com/2012/06/16/4557398/gardenings-busy-season-starts.html#storylink=cpy

For more on pesticide interactions: http://www.extension.org/pages/61004/miticide-and-fungicide-interactions




Dwarf butterfly bush is a great new addition to the dry, sunny flower border. Shown here with Euphorbia Ascot Rainbow is the variety Buzz Purple. These compact shrubs grow to three feet or so with equal spread. Butterfly bushes bloom on new growth, so they can be trimmed or cut back as needed. Hummingbirds and butterflies love them.


Here is the Buzz Buddleia in front of a more typical butterfly bush. The tight growth habit, with smaller leaves, leads to a mound of grey-green leaves and continuous purple flowers from spring through summer. These new dwarf hybrids are sterile, so blooms are more abundant (no energy going into seed production), and they won't reseed.


As of late June, our Clematis Ville de Lyon has been blooming since late May and will continue for another couple of weeks. The flowers are followed by interesting seedheads. Clematis like soil that has been enriched with compost, and the roots prefer shade. But the tops can grow up into full sun, or will bloom adequately in partial shade. Established vines can give dozens of blooms over several weeks, with varieties that start in early spring and others blooming in summer.



Clematis montana hybrids bloom in spring, usually March to April. The blossoms are smaller than later hybrids, but more abundant. The blooms smell lightly of vanilla. The Montana hybrids are unusual in that they bloom on old wood, so they should be pruned only after they have finished flowering. The pink flower shown is C. montana Mayleen, and the white one is C. montana grandiflora.


The Viticella hybrids bloom mid-summer, after most other Clematis are done. This plant, a variety called Polish Spirit, is scrambling all down a Nandina hedge on the north side of my house, and provides dozens of blooms over several weeks. Clematis naturally like to grow behind other plants, climbing up onto shrubs, trees, or climbing roses. They are light and open, so they don't suffocate the plant that is supporting them.


It's called Irish moss, and it looks like moss, but students of botany will recognize that it can't be a true moss: mosses don't flower! It's actually a ground cover in Caryophyllaceae, the carnation family. Irish and Scottish mosses prefer full sun.


For a mossy-looking ground cover for moist shade, try Baby's tears. It looks delicate, but can actually spread pretty freely in the shade. Baby's tears won't tolerate direct sun, and may frost back a bit in winter (but aways recovers). Great around stepping stones or with ferns and woodland flowers.

Wednesday, July 4, 2012

Succulents and Cactus!

Succulents have always been in my life.

We were the only ones with a cactus garden in our front yard. My parents were way ahead of their time for a water-appropriate Southern California landscape. Actually, it is a succulent garden, including cactus. Some were fuzzy, some showy, and a few were really spiny. Lots of kids encountered the latter during neighborhood games of kick-the-can.

I vividly recall backing into the business end of a century plant's spine once. In the front my folks had planted 5 or 6 century plants (Agave americana) in the early 1950's. A couple of decades later these all flowered at once, with 30' spikes opening into giant candelabras of blooms wildly attractive to bees and hummingbirds. After flowering the main plant dies, creating a giant cleanup mess, though several new 'pups' have usually formed at the base to replace it. But we pulled out most of them at that point � with a Jeep and a chain.

Once that was all cleared out, my mother kept planting interesting succulents and cactus. Some of her plants came from my grandfather. With a greenhouse in Pasadena and a garden in Palm Springs, he was an ardent cactus collector who also dabbled in other succulents. One of my reference sources for this is The Cacti of the United States and Canada (Lyman Benson, 1982), which he gave me with great pride as he had provided several of the photographs to the author.

When mom turned 50, I gave her Jacobsen's Lexicon of Succulent Plants and she was off and running. Rekindling her interest, she began collecting and propagating. Then she discovered that local nurseries would buy flats of them. Additional greenhouse space was built on their suburban lot. She finally phased back the production part a couple of years ago. At one point she confided in me that The Manual had turned out to be her most significant birthday present. Flowers and candy? Ha!

So you'd think I'd have written about succulents and cactus by now, pretty much having been hard-wired for them. And suddenly succulents are popular again. It's easy to see why.

  • Interesting colors and textures.
  • Low water use. Replacing your lawn with Sedum spurium or Delosperma cooperi could save over 15,000 gallons of water a year (but you can't walk on it much).
  • Spectacular, sometimes bizarre flowers. Asclepiads trap pollinators in cage-like flowers. Stapeliads smell like rotten meat to attract flies for pollination.
  • Easy to grow. They can go weeks without water.
  • Ridiculously easy to propagate.

A stem stuck in dirt will grow, or often just a leaf. I remember my son watching his grandmother "sticking" cuttings, and he asked in wonder, "so I can just stick this in dirt, it'll grow roots, and someone will buy it?" Welcome to the nursery business, my boy.

They are slowly shedding their reputation as collectors' plants, or something gathering dust in a pot in grandma's garden. I am happy to see succulents moving out into the regular landscape, providing a foliar foil for grasses and Agapanthus, or providing little points of contrast among annual and perennial flowers.

Succulents are plants which store water in modified stems and leaves. It is an obvious adaptation to dry climates, and succulents are heavily distributed in the "horse latitudes:" the subtropical latitudes about 30 - 35 degrees north and south of the equator, where winds are light and the weather is relatively dry. Most of the world's great deserts are in the horse latitudes.

Since we're a little north of that latitude (at 38 degrees N), it is important to know which of the succulents are subtropical and need winter protection. Some well-known succulents need to come indoors before frost, or be grown in a protected microclimate:

Aloe vera:
    grown for the medicinal leaves. Other Aloes are hardy, but not this one.

Ceropegia linearis woodii (Rosary vine):
    heart-shaped leaves, strange fly-trapping flowers.

Crassula argentea (Jade plant):
    elegant container plant has several varieties.

Kalanchoe:
    some with fuzzy leaves (Panda plant, Felt plant), others with showy flowers; all are tender.

Senecio rowleyanus (String of pearls)

To simplify: before Hallowe'en move the fuzzies inside and the jades to the porch. Cold is bad, but cold and wet is worse as they'll rot. A screened porch protected from rain is a great place for a collection of succulents.

Lots of unrelated types of plants are succulents. To answer a common question: the difference between succulents and cactus is that all cactus are succulents, but not all succulents are cactus. Cactus are all members of one family: Cactaceae. Other succulents come from many families, ranging from lily to cucumber. Many plants have stems or leaves which store water, but aren't considered part of this group. Impatiens and begonias have "succulent" (i.e., juicy) stems. But they lack the thick cuticle, or skin, that protects the plant from drying and enables a true succulent to withstand long periods without water. One oddity about succulents? They can store carbon dioxide to transpire at night, producing oxygen when most plants are producing CO2.

Popular succulents such as Hen-and-chicks (Echeveria) are leaf succulents:

    The leaves are thickened to store water, often coated with light-colored powder or hairs that provide protection from sun. Those without such natural protection are better in partial shade here. Flowers range from very showy (Kalanchoe blossfeldiana) to insignificant.

Cactus are stem succulents:

    The stem has a large amount of soft living tissue to store food and water, and very little woody tissue. Cactus don't have leaves (with some exceptions), they have spines clustered on areoles. In the wild they have shallow, wide-spreading root systems. Early botanists measured one young, 5-inch-tall Saguaro (Cereus gigantea) whose roots had spread over 15' in all directions, at only four inches depth!

The roots can form water-absorbing root hairs extremely quickly, then lie dormant for months until the next rainstorm. This enables them to sit in a pot in your garden for many years with only occasional care; I have a cactus that has been in the same pot for 40 years. Many cactus have spectacular flowers, and most have fleshy, juicy fruit. Prickly pear fruit is delicious, but the spines must be carefully removed first!

Cactus spines provide sun protection, along with the same kinds of powdery coatings and fine hairs found in other succulents. Old Man cactus has extra-long white hairs as well as spines. Again, if the variety you are buying has unprotected fleshy parts it may be best in partial shade here.

Day-blooming cactus often have very showy flowers in shades of pink, red, or yellow. Look for Echinocereus, Lobivia, Mammillaria, Rebutia and more. Night-blooming types, pollinated by moths, usually have white or pale yellow flowers, often very fragrant, on very large plants.

Succulents, including cactus, can be grown as houseplants. They require the brightest light you have, and some may lose their color or coating in low indoor light. Paler growth and stretching are signs the light is too low. The biggest risk is overwatering. For indoor growing, plant in a fast-draining potting soil, either one made specially for cactus, or by adding 1 part pumice or perlite to 3 parts regular potting soil. You can mix a bunch of interesting types together in a pot to grow as a living bouquet of foliage, removing any that get too big. Or take cuttings as the plants get tall.

On the other hand, if you're growing them in pots outdoors, here's a trick to reduce how often they need water. Add some clean topsoil to the mix at about the same proportion as the pumice. It will help retain moisture, so you can go weeks (or months?) between waterings and the plant will survive.

Cold-hardy succulents for our area (Sunset Zone 14, USDA Zone 9) include:

  • Aptenia cordifolia (Red apples): a vigorous ground cover with red blossoms.
  • Echeveria (Hen-and-chicks)
  • Graptopetalum: large pinkish leaves.
  • Sedum (Stonecrops): one of the most useful groups of ground covers.
  • Sempervivum (Houseleeks): like little hen-and-chicks, great in pots.

Agave, Aloe, Euphorbia, and Haworthia vary as to hardiness.

Cactus are all from the Americas (with one weird exception), and range from the tropics to very cold northern latitudes and high elevations. Most can live outside here if protected from rain during the winter, so keep them under an overhang in the winter. The combination of cold and wet can lead to rot. Christmas cactus are semi-tender, about as hardy as Jade plants.

Note to parents:

    some members of the genus Euphorbia have very irritating sap. Certain cactus contain toxins and hallucinogens. If your kid gets interested in cactus and other succulents, you may wish to monitor which species he or she collects.

There is an excellent collection of succulents open to the public right here in Davis, at the Botanical Conservatory at UC Davis. Visit http://greenhouse.ucdavis.edu/ for more information.

Oddities:
Caudiciforms are a weird group of water-storing plants that have woody enlarged stems (caudex), sometimes getting quite large. With age these can get very large and quite valuable.
Examples: Adenium obesum (Desert-rose), with oleander-like flowers (it is related, and also has poisonous sap like oleander).

Neither of these are true palms, despite the common names:

  • Beaucarnea recurvata (Ponytail palm)
  • Pachypodium lamerei (Madagascar palm)

Other caudiciforms have extra-large surface bulbs, from which new growth sprouts seasonally. People who get really serious about succulents and cactus tend to also collect caudiciforms because of the bizarre swollen stems.

Cresting, or fasciation, is a natural mutation of the growing point of a plant, occurring for unknown reasons in many types of plants. I've seen this flattened, distorted new growth on species ranging from fruit trees and roses to a hollyhock (the flower stalk flattened out, then split in two parts which coiled away from each other to create a Dr. Seuss mallow!). Because of the center-out growth habit of some cactus and euphorbias, this can cause interesting distortions. Which, of course, increases their value to collectors.

Tuesday, June 5, 2012

You Can Grow That!

The 4th of each month is You Can Grow That day! Here's what all the bloggers came up with this month.... http://wholelifegardening.com/blog/2012/06/05/garden-bloggers-you-can-grow-that-day-june-2012/

Monday, June 4, 2012

Ten Plants for Early Summer!


Click on any image for a larger version
Slide show of the plants in this article: Click here
As we head into summer, gardeners may be looking for plants that give lots of landscape value with little input. For ease of growth, abundance of bloom, and interesting foliage, here are ten plants I keep coming back to in the months of May and June for garden performance.

1. Buddleia Royal Red (Butterfly bush)
Butterfly bushes draw butterflies, hummingbirds, and bees. They have fragrant flowers, and are reasonably drought tolerant. The new Buzz Buddleias are dwarf, fitting into smaller yards and borders. But I still think Royal Red, which is actually purplish-red, is one of the best for its vibrant color.

2. Canna Tropicana (Canna lily)
I don't even really like Canna lilies for the most part. Ok, they impart a bold, tropical look, but they can look pretty scruffy after the bloom, and the rhizome roots keep pushing outward to make unwieldy-size clumps. But Tropicana has beautiful striped leaves. Great in containers, near water features, or in a border deep enough to accommodate some spread. The bright orange flowers are a nice bonus.

3. Cotinus coggygria (Smoke bush)
This is becoming one of my favorite small trees for patios, dry landscapes, and hot locations. Royal Purple has the most vivid colored leaves. A great substitute for the ubiquitous red-leaf plum, with a more graceful, open habit, and more tolerant of drought. The flowers are in wispy clusters, causing a "smoke" effect. There is also a gold-leaved variety.

4. Hemerocallis Gentle Shepherd (Daylily)
More than 60,000 cultivars of daylily to choose from, and I like this white one? Yes! The clean, creamy-white, very large blossoms are a departure from the usual oranges, reds, and yellows of daylilies, blending with any other color in the landscape. But there are gaudier colors if you prefer. Anybody can grow daylilies!

5. Hydrangea quercifolia (Oakleaf hydrangea)
Grandma's mophead hydrangeas, the giant-flowered types in pink or blue, are fussy in Davis. They get anemic due to the water quality, and require lots of water. The white-flowered Oakleaf hydrangea is a very elegant substitute. It doesn't care about the pH of our water, the foliage is very attractive (and turns a nice red color in fall), and the plant is much more refined than the mopheads. Prefers afternoon shade.

6. Lavandula x intermedia Grosso (Lavandin, hybrid lavender)
Lots of lavenders to choose from, but I especially recommend this one for fragrance and heavy bloom yield. It grows 3 to 4 feet tall and broad. All lavenders are heat-loving and drought-tolerant; in fact, it is easy to over-water them. Keep them dry once established. Grosso, like many of the hybrid lavenders, blooms from May through summer, often into fall.

7. Melianthus major (Honey bush)
Big bold-toothed grey-green leaves, mahogany-colored flower spikes in May. The foliage smells odd, not unpleasant; some say like pasta. Tolerates hot sun, partial shade, drought. Sprawls several feet across if allowed to, but can be cut back periodically for size control.

8. Penstemon heterophyllus Midnight (Summer snapdragon)
Penstemon is one of my favorite perennials, and Midnight is my favorite penstemon. Some varieties aren't long-lived; this one is. I have one plant that is more than ten years old. This is one of those May through July perennials, but it will give another fall bloom if you remove spent bloom spikes. Hummingbirds and the big solitary bees love penstemons of all kinds. Full sun or partial shade, tolerant of drought or average watering. Give 'em room: each of my plants is about 3 feet across.

9. Phlomis fruticosa (Jerusalem sage)
This is a big, sprawling shrub with attractive fuzzy grey-green leaves and strange, beautiful yellow flowers in whorls over a long period. The flowers smell exactly like carnations! Very drought tolerant, very sun tolerant, moderately shade tolerant. Branches can be allowed to root if you want it to cover territory. If not, cut it back now and then.

10. Punica granatum (Pomegranate)
One of the easiest fruit trees to grow, pomegranates always remind me in May and June how attractive they are in the landscape as they sport large, bright orange-red flowers. Then they remind me again in fall as the leaves turn bright yellow and the vivid red fruit ripens. Even if you don't eat the fruit, it is a beautiful landscape shrub or small tree. Pest-free, drought and heat tolerant. Dwarf varieties that set miniature fruit are useful landscape ornamentals.

-- runners up --
11. Achillea (yarrow): lots of new varieties with shorter stature and brighter colors have brought this old perennial back in popularity.
12. Alstroemeria (Peruvian lily): finding new use as a garden perennial, rather than just for cutting, due to a whole spate of new compact varieties.
13. Celosia (Plume flower and cockscomb): psychedelic color range, strange crested forms make these sun-loving annuals favorites for kids.
14. Euphorbia Ascot Rainbow: colorful foliage, chartreuse flowers, compact habit, full sun. Great with succulents.
15. Phygelius capensis (Cape fuchsia): elegant hanging flowers on tall open spikes attract hummingbirds all summer. Not a fuchsia! Much easier and hardier.





Buddleia is the genus of Butterfly bushes, a group of shrubs tolerant of sun, heat, and moderate drought. Old types grow 6 feet tall or more, and benefit from a hard pruning every year of so. Royal Red, shown here, isn't really red: it is purple with a tinge of red in each small blossom. Fragrant, free-blooming, and very attractive to hummingbirds as well as butterflies.


Canna lilies are noted for their bold, tropical foliage and gaudy flowers. They spread by rhizomes to make large patches. Tropicana has especially attractive striped, colorful leaves, and vivid orange flowers.


Oakleaf hydrangea is becoming one of my favorite shrubs for shady landscape areas. Elegant growth habit, attractive foliage, nice fall color, clean white blooms. A great substitute for the standard hydrangea, which doesn't like our water.


Honey bush is a big, dramatic plant in the landscape! It can tolerate sun or light shade. Interesting for large containers as well.


Penstemon, sometimes called Beard tongue, is a summer-blooming perennial that is attractive to hummingbirds and large solitary bees. Newer hybrids may have brighter, splashier colors, but Midnight is a proven performer in Valley landscapes. Plants shown here are three years old: 3 feet across and tall, blooming from May through July.


Jerusalem sage isn't a true sage, but it's a close cousin. A big plant for sunny locations, growing to 4 feet tall and 5 feet across, but readily trimmed for size. Fragrant blossoms, easy to root, easy to grow.


We need to start thinking of pomegranate trees for their ornamental value! The flowers are large and showy in May, fall leaf color is bright yellow, and the fruit is bright and colorful in fall. I water my pomegranate tree about once a month. The fruit is delicious, and if you don't happen to eat it the songbirds will.


Achillea (yarrow): the variety shown here is Strawberry Seduction, which blooms at about 18 inches tall from summer through early fall. Yarrows attract beneficial insects, make lovely dried flowers, and spread slowly by short rhizomes. Full sun is best.

Written for the Davis Enterprise, May 31, 2012

Sunday, May 6, 2012

Check out all the great posts at May's
! An informal project of garden writers, bloggers, and garden center owners.

Friday, May 4, 2012

You Can Grow That! May 2012: Sunflowers!



Sunflowers!


"Good mornin'.
You sure do make it like a sunny day.
Sunflower
fair warnin'.
I'm gonna love you if you come my way."
--Glen Campbell, 1977

I listened to that song repeatedly as I drove across the western states in the summer of 1977. It was Glen Campbell's last top-10 hit, and it dominated the country-western airwaves that year. Between California and South Dakota in the summer of 1977, the ONLY airwaves were country-western. To this day, I frequently burst into song at the sight of a field of sunflowers, much to the chagrin of my kids.
Fields of sunflowers have become a lovely and common sight in Yolo and Solano counties in recent years. Sunflower acreage increased 44% between 2003 and 2004, to over 13,000 acres, with farmers growing them for production of certified seed. Many of the fields that used to be in processing tomatoes now give us glorious blooms in July and early August.
From an aesthetic standpoint, this is a big improvement! The fields are a photographer's delight. Sunflowers also draw beneficial insects and are pollinated by many species of native bees. At least 29 species of native bees have been found visiting sunflowers in fields in Yolo County, especially species of long-horned and sunflower bees, followed by bumble bees and sweat bees. Most of these are ground-nesting solitary species.
In fact, the native bee species are more effective sunflower pollinators than honey bees, and they even make the European honey bees more effective. Why? European honey bees tend to specialize in nectar or pollen, and the two types of sunflowers planted in commercial fields – being male or female varieties -- have mostly one or the other. So the honey bees mostly stick to one type of flower. But the native bees bully the Europeans, chasing them between the rows, and making them up to 10 times more productive! Typical aggressive Americans.
Helianthus annuus is a western North American native. Western Native Americans domesticated it, with archeological evidence of cultivation as early as 2300 B.C. So it would even predate the Three Sisters (corn, beans, and squash). Sunflowers were used for food, dye, face-paint, oil, hair treatment, and even wart removal, snakebite and sunstroke treatment.
The plant was introduced to Europe and became very popular in Russia, where sunflowers were bred for their oil content (28 – 50% oil). Sunflower oil has been researched as an alternate fuel source, having 93% of the energy of US #2 diesel fuel. Russian varieties were re-introduced back into Canada and the US for vegetable oil production.
There are many varieties for oil, seed, and flowers: an agricultural research station at Iowa State has a repository of over 2,000 varieties. In the last twenty years three new types of sunflower varieties have been introduced. Dwarf varieties include Sunspot and Teddy Bear, each 12 – 18' tall. These are great for containers, and fun for kids to grow.
Cutting varieties branch, producing multiple (but smaller) flowers, and come in colors including red, mahogany, pale yellow, and white. Good examples are Italian White, Indian Blanket, and Parasol Mix. Some are pollenless, a real advantage for cutting since sunflower pollen stains fingers, fabric, and surfaces. Good pollenless varieties include Prado Red (rich garnet color) and Velvet Queen (a 'combination of bronze, burgundy, chestnut red, and mahogany' – Sunset Western Garden Book).
The sun 'flower' is actually a composite structure made up of 1,000 – 4,000 little tiny flowers (florets), compressed onto a flattened stem. Typically there are showy ones along the edge, which are male or 'ray' flowers, surrounding female or 'disk' flowers in the center of the head. Each disk flower has a little nectar to draw the bees; hummingbirds are also very attracted to them.
Why does the sunflower face the sun? The reaction is called phototropism (light+movement). An internal hormone called Indole acetic acid regulates this process. IAA is the hormone in plants which stimulates cell growth and enlargement wherever it is located in the plant. It is very light-shy and very mobile within plants. At night it is all throughout the plant. In the morning it migrates to the shaded west side of the plant, causing the stem to stretch gradually to the east, and in the afternoon this reverses. This continues until the stems become woody.
Sunflowers are incredibly easy to grow in all climate zones! Plant in full sun. They germinate fastest in warm, loose soil. But seedlings can actually tolerate some frost, so in the Sacramento Valley seeds can be started as early as February and planted out in March. Or they can be sown directly in the ground as late as August.
For the tallest plants and biggest flowers, plant in April or May into soil you've enriched with compost and fertilizer, and water frequently. The standard variety for competitive size and maximum production of quality seeds is Russian Mammoth, a variety that's been around for over 140 years. But sunflowers can be planted into mid-summer for pretty flowers, for cutting, and for seed production, and don't require special soil or care. You can just leave the plants to make seed and topple over, and songbirds will thank you.
There are a couple of sunflower relatives worth mentioning, both very easy to grow in full sun and pretty much any soil. Helianthus multiflorus is a hardy perennial that can be grown in every climate zone in North America, with many-branched stems topped with 3-inch sunflowers. There is a double-flowered form. H. tuberosus is the Jerusalem artichoke. This common name mystifies me. It isn't from Jerusalem: it is native to eastern and central North America. And the part you eat doesn't look or taste anything like an artichoke. It is a starchy tuber with a texture like a potato and a slightly nutty flavor. The plant grows to 6'+, with bright yellow single sunflowers, and spreads – shall we say? – freely.


Sunflower
good mornin'.
You sure do make it like a sunny time.
Sun mornin'
good mornin'.
And some da child
I'm gonna make you mine.
(repeat'and repeat'.and repeat'.)

Friday, April 6, 2012

You Can Grow That! for April

Check out all these great blog posts in the You Can Grow That! site for April! This is an informal project of writers, bloggers, independent garden center owners, and other garden enthusiasts.
http://wholelifegardening.com/blog/2012/04/04/garden-bloggers-you-can-grow-that-day-april-4/

Wednesday, April 4, 2012

Rosa banksiae, the Lady Banks Rose: You Can Grow That!


Walking the dogs down the county road at sunset, my son and I came to a stop to identify the fragrance that had suddenly surrounded us. If you’ve been to the county fair, you know the smell of cotton candy. If you had a grandmother that used violet water, you know that faint sweet scent. Put them together, and that was the invisible cloud we had just entered.
“What is that?” he asked.
“The Banks rose in the back yard,” I replied.
“But,” he said.
Yes, I know. The back yard is over five hundred yards away.

Many plants create compounds that volatilize under certain conditions; heat brings out the fragrance of lavender, Brugmansia and Cestrum nocturnum are only fragrant after dark. And many, like the Lady Banks rose, release their aroma at twilight.
You Can Grow That? Pretty much anyone, if living within the hardiness zones, can grow Rosa banksia. If they have enough room.

This is one unusual rose. No thorns. Evergreen. And it only blooms for about three weeks each year. But for those weeks the small blossoms are so abundant you can’t even see the foliage. It climbs by arching and clambering up, over fences, up into trees.
A single plant can cover thirty to forty feet of fence (mine does), or fully engulf a tree. In fact, the largest rose in the world is the Rosa banksia in Tombstone, Arizona, which covers over 8,000 square feet. But it can be pruned. One of my favorite examples is a specimen in downtown Davis (CA), across from Union Bank, which has been trained as a “tree” on two stakes, and has been severely pruned that way for as long as I can remember. It is being kept at about eight feet tall and broad!

The Sunset Western Garden Book tells us that it grows in Sunset Zones 4 – 34, and both zones in Hawai’i. In USDA parlance, that apparently equates to Zone 7a. So here in the Sacramento Valley (Sunset 8, 9 and 14; USDA 9) it is perfectly hardy.

There are three cultivars that I’ve seen, only two of which are in the trade, and not many wholesale growers produce the Lady Banks rose. You may have to search a bit for it.


Rosa banksiae ‘Alba’ is the white, double-flowered form. Flowers are showy, but fragrance is light (some might prefer that).

R. b. ‘Lutea’ has pale yellow, double flowers. It is more fragrant, and less common.


I have the white single-petaled cultivar, R. banksia normalis, which some references say “is believed to be the original wild form.” It is most fragrant of all, and very uncommon in the nursery trade. I got mine at a swap meet of heirloom rose growers in the 1980’s.


Note: a supposed variety called Snowflake has been in the trade for a couple of decades. It is a hybrid with another species, and is easily recognized by the thorns. True Lady Banks rose is thornless. The bloom habit is less abundant, but over a longer period, and it is not fragrant. If you’re expecting the profusion of Lady Banks, you’ll be disappointed. And the thorns are especially nasty.

For more on the Tombstone Rose: http://www.helpmefind.com/rose/ezine.php?publicationID=654&js=0

You Can Grow That! is a grass-roots project of independent garden centers, garden bloggers and writers, and other plant professionals!