Holiday houseplants are typically in postcard-perfect form when they come into our homes.
Poinsettias are plumped out in traditional red. Amaryllis bear giant, striped trumpets that blare “Look at me!” And Christmas cactus and cyclamen flash impossibly iridescent flowers in shades of red, pink and white.
But after New Year’s, those beauties start becoming bedraggled. Eventually we’re faced with whether to keep them or toss them.
Before you make that decision, it’s useful to know what kind of effort is required to sustain the plants.
It’s also important to realize that despite your most valiant attempts, some holiday houseplants simply will not return to their former stunning selves unless you replicate the extraordinary steps that commercial growers take, which include the use of greenhouses, grow lights, shade cloth and tight control over temperatures at various times during the plants’ life cycles.
That said, here’s what to expect.
Poinsettia (Euphorbia pulcherrima)
Between 35 and 40 million of these vibrant shrubs are sold in the United States during the holidays, and the lion’s share are sure to be discarded after Christmas.
For most of the country, that’s probably the right call, since poinsettias are native to southern Mexico and detest cold weather.
However, here on the Central Coast, they will grow outdoors if you provide them with sun and moist, fast-draining soil, and protect them from wind and freezing temperatures. Just don’t expect yours to bloom at Christmas. Longer nights trigger the coloring, and commercial growers manipulate the light in greenhouses. Left to nature, yours may not show color until January. Planted within the glow of a porch light or street light, it might not color up much at all.
In addition, your compact indoor plant is likely to become leggy outdoors, easily reaching 6 to 10 feet tall.
If you are determined to keep your poinsettia compact and force it to rebloom in December, don’t plant it in the ground.
Instead, keep it in a pot and place it outdoors in a sunny spot. After the leaves drop, cut back the stems to 6 inches tall, leaving at least two joints on each stem. Water when the top few inches of soil dry out, and pinch back new growth every few weeks to encourage fullness.
The special light regimen begins in mid September to early October. Every night for eight to 10 weeks, move the pot into a dark closet for 14 hours, say from 6 p.m. to 8 a.m. Every morning, move it into sunlight for the day. That daily cycle of 14 hours of darkness, followed by 10 hours of sunshine, should produce the most vivid holiday color.
These impressive, giant bulbs, bearing large, showy trumpets, are an increasingly popular Christmas item. But once again, growers have manipulated their bloom time.
In the garden, amaryllis bloom in the spring, right before or just as their broad, strappy leaves emerge. Having just bloomed over the holidays, yours is not likely to replay the show this spring. Instead, you’ll have to wait about 15 months for the next round of spectacular, candy cane-striped flowers.
After the new year, set your amaryllis outside in the sun and water it occasionally. Make sure the container has drain holes. If not, make some, or transplant the bulb to a porous clay pot filled with fast-draining cactus mix. The pot should be on the small side, with just an inch or two of space between the side of the pot and the rough, papery edges of the amaryllis bulb. Plant the bulb high, with up to half of its top exposed.
With filtered sunlight and occasional water, agapanthus-like leaves should emerge in spring. When the leaves begin to yellow, stop watering and let the bulb and foliage dry out over summer. Flower buds form, deep within, during this rest period. New, succulent flower stalks should then rise and bloom the following spring.
Christmas Cactus (Schlumbergera)
These sparkly plants share poinsettias’ need for controlled light. But they take only six to eight weeks of going dark for 12 to 14 hours, rather than eight to 10 weeks for a solid 14 hours. Again, that includes blocking any exterior, night-time lighting.
Fortunately, the shorter time frame means that even without any help, your Christmas cactus should bloom during the holidays. But if you still insist on controlling the light to ensure flowers at a particular time, it’s best to leave the plants outdoors and cover them with paper bags each night. Otherwise, they might balk at the twice daily moves and shed their buds in protest.
Whatever you choose to do, after Christmas, move your Christmas cactus outdoors to rest in a spot with bright, indirect sunlight. Mine is packed into a hanging basket. I hang it on a lower branch of a purple-leaf plum tree. The tree is bare over winter, when sun protection isn’t all that important. Then it leafs out to provide filtered shade during spring, summer and fall.
Christmas cactus truly are members of the cactus family, and are at their best in containers with extremely fast-draining soil. Hanging baskets are especially effective, because as the cactus gains size, its jointed arms can gracefully cascade over the sides.
Water yours occasionally, letting the top inch of soil go dry between waterings. Don’t let the fleshy leaves shrivel up.
Cyclamen (Cyclamen persicum)
These perky little clumping plants, with heart-shaped leaves and flower petals shaped like flames, are being increasingly marketed as holiday houseplants.
However, they prefer temperatures much cooler than we usually keep our houses, and are at their best indoors next to the draftiest, coolest window possible.
After the holidays, move your cyclamen outdoors to a spot that offers the same filtered shade that Christmas cactus appreciate. But rather than transplanting your cyclamen to hanging baskets, leave the plants in their small pots or put them in the ground, provided you have excellent drainage.
Cyclamen grow from tubers, the tops of which should sit slightly higher than the surrounding soil. They are native to the eastern Mediterranean region, which shares our climate of warm, dry summers and cool, wet winters. The tubers go dormant over summer and need dry soil during their rest. New leaves will begin to appear in fall, followed by flower buds that will bloom in winter and spring.
Most holiday houseplants prefer bright, indirect light indoors, and cool temperatures. Keep them away from south-facing windows and heater vents.
Watering can be tricky. In cooler rooms out of direct sunlight, the soil may stay damp for a week. But in a bright spot or within range of a heater, they may need water almost daily.
Also, because holiday houseplants tend to spill over the edges of their containers, it can be difficult to poke the soil to see if it’s dry. Instead, use the lift test — water your plant thoroughly, then lift it to see how heavy it feels when the soil is saturated. Check it every few days, and when it feels considerably lighter, it’s time to water again.
When you do water, stop when you see water beginning to trickle into the pot saucer. Empty the saucer so that the bottom of the plant doesn’t sit in water.
Seeds of Wisdom
If you’re still hunting for a quick gift, consider a poinsettia, amaryllis, Christmas cactus or cyclamen. Given the proper conditions and care, all should live long after the holidays, out in the garden.
Visit Joan’s website at www.SantaBarbaraGardens.com, or post a comment by clicking on “Leave a Comment” back up at the top.