Holiday plants decorating our homes and offices keep the Christmas spirit alive. But the challenge is to shower yuletide plants with tender loving care so the poinsettias, amaryllis, cyclamen and kalanchoe will stay alive and flower another holiday season.

Here's how to meet the challenge:

Poinsettias are doomed if they stand in full, direct sunlight. Instead, provide bright, indirect light, avoid drafts from heat registers and keep the soil lightly moist. Maintain good nitrogen levels in the leaf tissue by using Peters' 20-20-20 plant food every time the soil needs to be moistened; when you rest your finger on top of the soil and it feels dry, apply Peters right away. Let the soil drain for 15 minutes in the sink, then return the plant to its former location.

Average room temperatures are fine, but the closer the mercury is to 60 degrees, the longer the colorful leaves will stay on the plant. At temperatures below 60, roots will probably begin to rot.

If you have a poinsettia from a year ago, don't be disappointed if the leaves failed to color up this Christmas. Continue your care program without moving the plant. Your poinsettia will begin to color up in February, and a handful of leaves will be in place by Washington's birthday.

Amaryllis is unquestionably the most spectacular flowering plant over the winter, and justifiably so with its six- and seven-inch diameter, trumpet-shaped blossoms. As the stalks and flower buds develop, keep the plant in full, direct sunlight up close to a south-facing window. At night, pull the shade or blind, and rotate the pot a half-turn.

When the flowers unfold, immediately move the plant out of direct sunlight and into bright indirect light, and leave it there until the flowers wither, at which time you should cut the stalk back to where it exits the tuber, and return the plant to full, direct sunlight to force more blossoms.

Keep the soil lightly moist, generally applying lukewarm water every three or four days. Rest your finger on the soil; when you sense it starting to go dry, water the next morning. Apply Peters' 20-20-20 every other watering to maintain high energy levels in the plant.

Continuous flowers should develop through late March or early April, after which leaf stalks will emerge from then up to the last days of summer.

Cyclamen is the most underrated of all winter flowering plants, probably due to unfamiliarity by indoor gardeners. You will never be disappointed with it. Blossoms come in most colors of the rainbow, but it's the unique "butterfly design" of the flowers that's captivating. Cared for properly, the plant will produce round after round of delicate flowers from mid-November well into April when the plant goes dormant for the summer.

To care for a cyclamen from a garden shop, first let the soil begin to dry and let it go dry for one more day before moistening the soil with warm water. Display the plant in medium, indirect light -- never in full sunlight -- in average room temperature during the day, and move it to a cool room for the night. Return it to the warm room the next morning. If you have a naturally cool room, the plant can be kept there from here on without moving it at night. In a cool environment, you may only have to wet the soil every 14 days or more.

Fertilize with Peters' 20-20-20 every other watering from now through early March, after which you should apply plain warm water.

Norfolk Island pine can be kept at average room temperatures over the holidays, but they must be moved to a cool room with temperatures consistently in the 45-55 range after New Year's. The pine must have cool temperatures and humidity higher than above 45 percent over the winter. Otherwise, the lower branches will turn brown before spring.

Medium indirect light is sufficient. Keep the soil lightly moist over the winter, but in cool rooms you will probably water the soil every two-plus weeks. Apply no fertilizer until early April, then apply it each month afterward.

Kalanchoe is easy to care for. Provide full, direct sunlight for half the day, bright light for the rest. Average room temperatures are fine. Allow the soil to begin to dry before watering, usually every 10 days in winter. Each month, feed with Peters' 15-30-15 diluted to half potency.

Jerusalem cherry is usually discarded after the holiday season in favor of more worthwhile plants. Meanwhile, keep the plant in medium light in average room temperatures, and keep the soil evenly moist at all times; use Peters' 15-30-15 at half its potency whenever the soil needs to be moistened.

If you displayed a balled-and-burlapped Christmas tree indoors over the past week, it's a good idea to move it out of the house before this day is over. Remove decorations and lights and scatter a thick layer of newspapers on the floor before lifting the root ball from the tub. With one person holding the top and the other grasping the root ball, move the tree outdoors. Fetch the tub and rubber tire, moving them to the garage if possible, otherwise to a protected spot outdoors. Move the root ball atop the rubber tire, then add your daily quart of warm water to the root ball, and spray the needles with warm water.

Continue this for the next week, then plant the tree according to the garden shop's or nursery's instructions.

If you normally take down the cut Christmas tree after New Year's Day, we suggest you consider the following:

Having removed all decorations, lift the tree carefully from the stand so as not to spill any preservative on the floor. Wrap the base of the trunk with newspaper, then carry the tree outdoors. Saw or prune every limb from the tree, scattering the boughs around rose bushes and atop the bulb and herb gardens. Saw the tree trunk into six-inch sections and throw them in the trash. If you used the homemade preservative, try lighting a small branch outdoors after pruning it from the tree. It won't burn if you did things right.

Jack Eden is the host of "Over the Garden Fence" Sundays from 10 a.m. to 1 p.m. on WTOP Radio (1500 AM).