Thursday, December 10, 2009

Those holiday plants!

What to do with those holiday plants?

Someone gave you a plant for the holidays -- now what?

Many plants have become associated with the holiday season, brightening our homes during these gloomy December days. If you think of most of these plants as nice, long-lasting flower arrangements that you will discard after they finish blooming, you won't be disappointed. Some, however, can be grown on for years with special care, and others can simply be planted in the garden. Parents of young children and pet-owners should be aware that some are poisonous.
The Poinsettia (Euphorbia pulcherrima) is remarkable in that in just 75 years it has become THE Christmas plant.

This roadside weed from Mexico has been bred (largely by the Ecke family in Southern California) to the point that nearly 100 million of them are sold worldwide every Christmas. This in spite of the fact that more than 60% of the public incorrectly believes them to be poisonous! The showy part of the plant is a bract, which is a leaf, and the flowers are the small yellow parts in the middle.

Care during the holidays:

Make your house like Mexico! The Ecke Ranch website ( states "if you are comfortable, so is your poinsettia." Poinsettias definitely don't like to be below 50F, and don't like drafts or cold winds. The brightest room in your house is best. Water just when they go dry, and tepid or warm water is better than cold tap water.

After the holidays:

Poinsettias will begin to drop leaves in February, and then will go dormant. You can reduce watering at that time, and as soon as frost is unlikely (late February) you can move the pot outdoors. Cut them back 50%, repot into a larger pot, and start watering. Start feeding with Miracle-Gro or a similar fertilizer as new growth begins.

Getting them to bloom again is tricky. From late September Poinsettias need 14 hours of complete darkness (not even exposure to a simple incandescent light bulb!) for several weeks to trigger blooming. ANY disruption of that photoperiod requirement will prevent blooming!
Kind of a hassle. -- What did you pay for this plant?
Just buy a new one next year!

Not at all!
Don't get me going.
Poinsettias are NOT POISONOUS!
No part of the plant is poisonous! Nursery people have even eaten leaves on TV to prove it!
No amount of leaves stuffed into lab animals was able to cause a toxic reaction, nor was any amount of application of the sap.

"Thom David, marketing manager of the Paul Ecke Ranch in Encinitas, California, has a way of convincing people ... . He's been known to grab a few bracts off the nearest poinsettia plant and eat them in front of persistent disbelievers. Seems to work, too - they don't doubt him after that.
Speaking from "bitter" experience, he says it's unlikely a kid or an animal will eat more than one bite. He describes the taste as far worse than the most bitter radicchio. Frankly, he says, the flavor is indescribably awful."

Holly (Ilex species, especially Ilex aquifolium 'Variegata') is enjoyed for the long-lasting, clean shiny foliage which is great in wreaths and arrangements, and the bright red berries.

Holly is an excellent garden plant that prefers protection from the hottest sun. Male and female plants of English holly are needed to get berries (and nurseries don't sell them by sex!), but some varieties of other species set berries reliably without cross-pollination. Often described as preferring acid soils, I find that hollies do well here without special attention if the soil is amended when they are planted and if they aren't drought-stressed. Avoid the hottest afternoon sun.

The berries are described as causing "minor toxicity" in the Regional Poison Control Center guide, and the botanical name of our native holly, Ilex vomitoria, gives an indication of the symptoms.

Ivy (Hedera helix) is being used more and more for winter greenery and as filler in winter arrangements.

The smaller-leaved varieties such as 'Needlepoint' or 'Hahn's' are preferred. Ivy can be grown into rings, wreaths, "poodles," cones, or other shapes. Ivy makes a great indoor plant if it is washed off periodically to prevent spider mites, and can be kept outside in morning sun or the shade of a tree. It is completely hardy in our climate, so it can live outside year-round. Ivies can become invasive if planted in the garden, so keep them in pots.

Yes -- leaves and berries cause major toxicity, and the symptoms are very unpleasant.

Amaryllis bulbs (Hippeastrum hybrids) are among the easiest plants to grow and bloom during the holidays, and have stupendous large flowers in shades of red, pink, and white.

Amaryllis naturally bloom in the early summer. These bulbs are produced in Holland and South Africa. Those from Holland have been forced into dormancy and will bloom 2 – 3 months after planting. Those from South Africa think they are in the summer, being from the Southern hemisphere, and will bloom right away.

Give Amaryllis water every few days until the bloom is done. Cut off the spent bloom spikes and allow the foliage to grow indoors until frost danger is past. I've had my best results simply planting these in the ground in partial shade or full morning sun, in average soil. They will bloom in future years in the early summer. Watch for snails! It is possible to get them to bloom for future Christmases by forcing them into dormancy in the late summer (withhold water), but it doesn't always work.

One reference: "The principal irritant is present in small amounts so large quantities of the bulb must be eaten to cause symptoms (diarrhea, nausea, vomiting)."

Pure white Paperwhite narcissus (Narcissus spp.) and their related varieties ('Soleil d'Or' is gold; 'Chinese Sacred Lily' is white with a light yellow center) are also very easy to bloom indoors for the holidays.

The fragrance is powerfully sweet!
This bulb multiplies very freely outdoors in the ground here. Keep watering the pot they are in, or the bowl, or whatever, until they finish blooming. The brighter the situation, the less floppy the leaves will be. After the holidays, stick them in the ground. They'll multiply freely in sun or light shade, and will increase for years. I'm still enjoying flowers from bulbs that old-time Davis resident and botanical illustrator Dr. Addicott brought me 20 years ago.

The bulbs can cause "major toxicity."

Kalanchoe blossfeldiana is an unpronounceable recent addition to the holidays (try Kall-ann-koe-uh).

Growers have developed varieties of this succulent with blooms in neon colors -- shades of orange, pink, cerise, and red -- which hold for many weeks. Too tender to be outside in the winter here, they can live in a pot with little care for months or years and need very little water. They won't bloom again as densely or compactly as the original plant did, but can put out sprigs of bright blossoms in the spring and summer. Keep these in the brightest part of your house while they are in bloom, and water only when dry. Transplant into a larger pot after it finishes blooming, and put in out in morning sun or the shade of a high tree after frost.


Azaleas (Rhododendron species) sold during the holidays are new varieties with a prolific, long bloom.

A little tender in our climate, so they might be damaged in freezing weather (unlike their hardier garden cousins). Typically they are grown in soil with a high amount of peat moss, which makes it tricky to water them correctly, and they are usually incredibly root-bound. If water just puddles on the surface, or runs down the side of the pot, the peat moss has dehydrated and the pot needs to be set in a bowl of water to rehydrate.
If you're going to plant these in the garden, amend the soil heavily with a soil mix that's special for acid-loving plants., and plan on fertilizing regularly with an "acid-type" fertilizer. Tear the roots apart as you plant them to reduce the root-bound condition. Water very carefully as we get into hot weather, making sure to water the root ball thoroughly about twice each week.

"Major toxicity," and the foliage may cause dermatitis (skin rash).

Mistletoe is an oddity.

This semi-parasitic plant grows entirely on other plants but also photosynthesizes to create food for itself. The mistletoe of Christmas is probably in the genus Phoradendron, as are several of our native mistletoes. A quick review of Munz' definitive California Flora describes it as a "large genus of the Americas," with the species Phoradendron tomentosum ssp macrophyllum on sycamores, poplars, willows, ash trees, walnuts, and persimmons [and birches] in the Sacramento valley and other areas." This is the one on older trees all over Central and East Davis, and certainly not the species the druids prized on their oak trees. Birds enjoy the berries and then spread them from tree to tree in their droppings.

My reference books were ambiguous, so an operator at the Poison Control Center (1-800-342-9293) commented that ingestion of a couple berries or leaves would lead to severe vomiting and diarrhea. She also referred us to an excellent web site -- -- for more information about poisonous plants.

Enjoy your holiday plants -- carefully!

Published in the Davis Enterprise, 28 December 2000

1 comment:

  1. Please be aware that some of your information is not accurate for dogs and cats! While poinsettias aren't poisonous (and overhyped), the Lillium species (easter lilies, tiger lilies, asiatic, etc.) are extremely poisonous and one leaf will kill a cat. Also, Kalanchoe is very toxic to pets and causes cardiac arrhythmias.

    When in doubt, call an ANIMAL poison control if you are worried about what your pet got into. You can find more information at or by calling 800-213-6680.


    Pet Poison Helpline