From Thanksgiving to New Year’s Day, millions of houseplants are used as gifts and decorations just to be dumped when holiday cleanup commences. That’s a nice boost to growers and sellers of poinsettias, Christmas cacti, amaryllis, paperwhites, Norfolk Island pines, rosemary, citrus and numerous lesser-used gift plants. As a thrifty gardener who really appreciates the holiday traditions which include live plants, I have always had mixed feelings about this aspect of the season. Some of these plants can be challenging to provide long-term care, but others adapt quite easily for use as houseplants or even landscape plants. Here are some thoughts on keeping these plants for the long haul.
Poinsettias may be the plant most associated with Christmas, and for good reason. The traditional giant red bracts and golden-yellow flowers viewed against the dark green foliage leave little to the decorator’s imagination. These are probably the most challenging for most of us to keep as houseplants. They are not terribly difficult to keep alive; simply provide bright light and evenly moist soil. The difficulty for those of us who live outside its native range lies in getting them to change color…here’s how:
Allow the poinsettia to go dormant by keeping it dry (don’t let the soil shrink from the sides of the pot, but allow it to dry between waterings), in a cool, bright room. In late spring, when night time temperatures are consistently above fifty degrees, prune it to a six-inch “stump” and move it outdoors. Through the summer, keep it in very bright light and fertilize regularly. When night temps get below fifty degrees in the fall, move it indoors. Make it change color by controlling light and darkness, beginning at least two months prior to when you want them to be at peak color. The darkness needs to be total: put it in a closet or cover it with a cardboard box for 13-14 hours each night. When the bracts begin to color, you can stop covering it and increase water to keep the soil moist.
Christmas cacti are not desert species, and they make good houseplants. They perform best in a cool, moist environment with bright but indirect light. For the best bloom show, pinch the tips when blooming ceases to encourage branching. Keep the plant indoors until the night temperatures are warm, watering when the soil is dry one or two inches deep. Move to a bright filtered-light location outdoors for the Summer, fertilizing regularly with blooming houseplant food while it is actively growing. When night temperatures drop in the fall, move back indoors. Blooming is stimulated by darkness: provide 12 hours of total darkness for six to eight weeks prior to when you want the plant to be in bloom.
Amaryllis are tropical and subtropical natives from fairly diverse habitats. To keep them over the long term, begin by keeping them cool and watering minimally as they bloom. When blooming ceases, cut the bloom stalk(s) just above the bulb. If it was forced in water only, move it to a soil filled pot with the top of the bulb exposed. Soon, if not already, leaves will appear and you can water and fertilize, keeping the soil moist (not wet!). When all threat of frost is over, move outdoors to direct sun, and maintain water and fertilization through summer. At the end of summer, stimulate dormancy by allowing the soil to dry out and moving the pot to a cool (55 degrees) location for eight to ten weeks. When the new flower spike is peeking out of the top of the bulb, repot it into a small container, about twice the size of the bulb itself, with fresh potting soil. (If new side bulbs have formed, they may be separated and potted separately but will not bloom the first year.) Water thoroughly after repotting and move to a warmer, bright-light location. Keep it moist through the bloom cycle, being careful not to wet the top of the bulb.
Paperwhites present a challenge because of their natural life cycle, which has been more completely disrupted than the others mentioned here. These relatives of daffodils are only hardy to zone 10, and do not require dormancy however they do require nourishment to replenish the energy used to bloom. You may be able to coax another bloom in two or three years by potting it in soil, feeding it, and giving it as much direct sunlight as possible.
Norfolk Island Pine
This tropical conifer may be the easiest option for a living Christmas tree, and is easy to keep as a houseplant over the long term. It will grow quite well in a bright room, and can get very large over time. If you move it outdoors for summer, a filtered light situation is best. Keep the soil moist and fertilize regularly with a general purpose houseplant food.
Rosemary is a popular holiday gift plant. Keep rosemary indoors on the cool, dry side in as much light as you can give it. During the growing season, keep it moist and fertilize with a balanced slow release fertilizer. In the south (zone 7 and higher), transition it outdoors to keep in a large container or plant it in the ground. In the north, transition it outdoors when temperatures are consistently above freezing and bring it back inside when a hard freeze threatens.
Citrus has long been associated with the holidays, and now citrus plants are increasing in popularity. They keep well in bright light, with consistent moisture and regular fertilization. In the Spring transition citrus trees outdoors, when all threat of frost is past, into direct sunlight. In fall, move them indoors when night temperatures approach the mid-thirties.
Nothing To Lose
If you are a “brown thumb” with no luck as a gardener, you have nothing to lose by taking a chance on a plant that was destined for the dumpster in the first place. Seasoned gardeners will welcome an opportunity to get their fingernails a little dirty during the Winter. Keeping these holiday plants alive and thriving is fun and may begin a new diversion for you in the new year. Happy gardening!