Wednesday, October 19, 2011


From the Davis Enterprise, October 28, 2004

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Bulbs have got to be the easiest things we plant in the garden, with the highest bloom:effort ratio. Dig a hole, stick 'em in, cover with soil, and water. The rains come along and do the rest. A few weeks later, up they come--growing and blooming without any more work by you.

Some technical terms.

'Bulb' is a generic term for modified, swollen stems. A true bulb has a set of overlapping, fleshy leaves, usually surrounded by dry, papery skin that protects it from drying. Cut a true bulb in half and it'll look somewhat like an onion on the inside (it'll also be useless after you do this!). Corms, rhizomes, and tubers are other modified stems that are sold as 'bulbs'. The primary function of each is to store food and some water, and each has one or more growing points to start new plants.

Bulbs are perennials, meaning they bloom again after the first season. Some repeat for a few years; others spread for many. Most are cold hardy. Subtropical types (paperwhites, freesias) need winter protection in colder climates, which is important to know if you are sending them as gifts.

How do you plant them?

It's so easy, even a child can do it. In fact, since it's down at the ground level and we are old and stiff, it might be better if a child did it. And bulb planting is a great thing to do with kids; it's nearly impossible to make a mistake.

--Dig a hole a little more than twice as deep as the bulb is tall--a 3" daffodil goes into a 6" hole. I generally dig holes wide enough for several bulbs, since a solitary bulb looks pretty lonely the first season, and plant them 3 - 4 inches apart. Exceptions: iris rhizomes are planted only half-buried. Amaryllis should have their necks exposed.

It's not necessary to mix compost in the soil, but the bulbs will grow and increase more quickly if you do. I've done plenty of bulb planting in soil that was too muddy to mix anything into. They'll be fine.

--Sprinkle some fertilizer in the bottom of the hole. It should have some nitrogen and a fairly high amount of phosphorous (those are the first two numbers on the label). Bone meal is popular due to the high phosphorous content, but it is very, very slow acting. Commercial bulb foods are better (specialty vegetable or flower foods are fine, too).

--Set the bulbs a few inches apart. The point goes up (this may seem basic, but it's pretty important!). Some bulbs don't have an obvious point, so look for the scarred area where roots used to be and put that side down. If you really can't figure it out, put it on what appears to be the side. Ranunculus are planted 'prongs down'.

--Cover with soil and water to settle the soil. That's it! Winter rains will take care of the rest.

It is ok to plant low-growing annual winter flowers right on top of the bulbs: pansies, violas, sweet alyssum, Cyclamen, and dwarf snapdragons all make excellent companions. Low ground covers are also great. The bulbs will grow right up through them to make a spring bouquet.

When to plant?

Anytime between September and early January. Tulips and Hyacinths shouldn't be planted until the soil has cooled, meaning after the end of October. If you find the bag of bulbs in your garage in January or February (we get these calls every year…), plant them. They'll still grow and bloom, albeit a little later than normal, and they'll be back on cycle the next year.

Bulb plants continue to grow for several weeks after they bloom, storing energy for the following year. If you cut off the foliage, you weaken the bulb. So let them die down naturally, though you can tie or braid the foliage if you want to look fastidious.

There's no need to dig up bulbs for the following year. If they've been in the ground for several years and are blooming less and less, it may be time to divide them. Or they may be getting too much shade. In either case, just after (or as) they die down is a good time to dig them. Replant them right away, or store them in the garage until fall.

It used to be recommended to put tulips and hyacinths in the refrigerator for 4 - 6 weeks before planting, but this is unnecessary. Just wait until the soil is cool. Pre-chilling WILL make them break dormancy and bloom all at the same time, so if you want your tulips to flower uniformly go ahead. Do NOT put them in the freezer (we get calls….). That kills them.

Some bulbs are planted in the spring for summer bloom--Dahlias, Gladiolus, and others. We plant those from February into the summer, depending on the type.

Which to grow?

Daffodils and narcissus

are the easiest of the bigger-flowered bulbs. At a minimum, they'll repeat their bloom for a few years. Some varieties will multiply, giving more flowers every year.

A note about the names: all are members of the genus Narcissus. Those with a single large flower (usually with a trumpet) are called daffodils. Those with small flowers in clusters are called narcissus. The fragrant ones with pure white blooms in early winter are paperwhites, a type of narcissus; there is a yellow form and another called the Chinese sacred lily in this category. Europeans call the whole group 'jonquils', but we use that term for a particular, small, fragrant narcissus. Confusing, eh?

Some good daffodil choices:

  • February Gold (short, very early dwarf trumpet; spreads freely)

  • Fortune (orange/yellow, spreads vigorously)

  • Flower Record (white with orange cup)

  • Ice Follies (white with pale yellow large cup; spreads vigorously)

  • Mt. Hood (ivory white)

  • Salome (pink, sort of)

  • Spellbinder (yellow with white trumpet--striking!)

Good narcissus choices:

  • Cheerfulness

  • Geranium

  • Pheasant Eye

  • Thalia

  • Yellow Cheerfulness

  • Miniatures: Baby Moon

  • Tete-a-Tete (one of the best!)

'King Alfred' was once a variety of large, yellow trumpet daffodil. It is now a generic name for that type; Unsurpassable and Early Splendor are newer, more vigorous varieties that will repeat and increase somewhat.


are very easy--both the large-flowered bearded types (grown from rhizomes) and the Dutch irises grown from bulbs. Not generally the most attractive garden plants, but worth the space for fragrance and cutting. There are also cute miniature types which bloom very early, and other species which can grow standing in water. A diverse group.

Tulips, hyacinths, and crocus

will bloom very nicely the first spring. The trick to getting them to bloom in subsequent years is to plant them where they won't get watered in the summer. Tulips with minimal summer water will repeat, though the flowers will be smaller, and hyacinths will increase. These latter have powerful fragrance reminiscent of Grandma's perfume. Giant Dutch crocus tend to peter out after a couple of years, but the species crocus will increase and bloom -- as early as late January here.

Some species of tulips come from Mediterranean climates similar to ours and will naturalize happily here. Tulipa chrysantha, T. clusiana, and others have miniature flowers on short stems. A half-dozen bulbs will increase to 2 - 3 dozen plants within just a few years. Grape hyacinths share the common name but are an entirely different plant (Muscari). These have short, purple flowers and spread very, very freely. The saffron of commerce is Crocus sativus--like some Mediterranean species, it blooms in the fall, and is easy to grow and increase here (coming as it does from Greece, a climate similar to ours).

'Minor' bulbs.

Many of these (i.e., small bulbs and flowers) spread to the point of being almost annoying. Cheap, easy, and prolific. Most can tolerate some shade, will spread through flower borders and even into lawns.

Some old favorites just don't get enough winter chilling to bloom again, including Lily-of-the-valley and Snowdrops (Galanthus). Freesias are popular for fragrance, and very successful. The old-fashioned yellow and white forms are most fragrant.

Good 'minor' bulbs for this area:

  • Allium (ornamental onions)

  • Brodiaea

  • Freesia

  • Hyacinthoides (Wood hyacinth)

  • Ipheion (Spring starflower)

  • Leucojum (Snowflake)

There's no hurry on getting bulbs planted after you buy them. They do their thing with little input from us. They announce the spring with colorful bursts in every hue. These little storage units have everything they need, lying dormant through winter cold or summer drought, ready to expand and grow when conditions are to their liking. What a great adaptation the bulb is--for us!