NOW that the tree leaves are falling, plant thoughts are moving indoors. But they need not be treeless thoughts. There are many indoor trees that can be grown in the home as a sort of substitute for the leafy canopy of summer.
Of course, office buildings, malls and banks are made all the more splendid with these indoors trees, which are used to make tall cold walls fit the human scale. But many of these same plant species can be utilized in the home. Exceptionally tall ceilings are not necessary in most cases. Nor are the fancy pots. Just choose plants wisely and care for them properly.
Before getting into plant particulars, a few words on their care. Caring for indoor trees is a bit different from tending geraniums and African violets. Unlike these little pots, the trees grow in bigger containers that hold plenty of soil, moisture and roots. Overwatering these big pots is probably the chief cause of trouble. Watering them once a week or maybe once every two weeks is ample. No hard and fast rules can be made because each home will be different, with variations in light exposure, heat and growing medium.
When grown indoors, trees that are overwatered often produce yellow leaves. The uninformed, thinking the plants are thirsty, water more, and worse, add soluble plant food to the watering can. Dracaenas and ficus are two commonly grown indoor trees that should never be overwatered lest they produce a crop of yellow leaves, or worse the roots rot.
In tandem with overwatering is overfeeding. It is tempting for novices to feed plants amply to force them into fast growth. Allow these indoor trees to grow at their own pace and feed them once or twice during the winter season.
Most of the indoor trees require some light. Those that need ample quantities include jade, dwarf orange, pony tails, pittosporum and fiddle-leaf fig. If these plants are not thriving where they are located, lack of sufficient light could be the problem. Move them to a brighter place. Morning sun is usually stronger in the winter months because the sun is lower and the rays are more direct.
Scheffleras do well in modest light as does the ever popular dumb cane (dieffenbachia). For darker corners there are two old reliables: dracaenas and many of the palms. If it can be found, the screw pine (pandanus) will thrive in low light levels, too, but it is better with bright morning or afternoon light.
As to pests, watchful eyes are important. Visit the plants often just to look at them and keep the leaves clean. (A wet paper towel is ideal). This sort of leaf cleaning is also a good way to examine plants and note what is going on. The sneakiest enemies are mealybugs. They have a quiet way of finding safe harbors in leaf axils and building up their population at an alarming rate. Keep cotton swabs handy and a bottle of rubbing alcohol. Go to work and wipe them out of these places. The mealybugs will be killed on contact, but check every few days to be sure.
As to the plants, the choices are generous and depend a great deal on what is available at the local greenhouse. Probably the most popular indoor trees now are in the ficus clan. The weeping sorts such as Ficus benjamina have come out in many fancy models. More recently those with braided or twisted trunks have become popular. Be sure to turn these fancy-stemmed ficus every week or so to keep the stems straight and to keep the growth even on all sides.
A newer edition of the weeping fig has darker leaves, which are longer and more graceful. These may be hard to find until more are propagated for the market. Look for them with the names of Alli or Citation.
Children (and adults) have become fascinated by growing avocados and citrus seeds into indoor plants, especially those seeds saved from the morning grapefruit. These seedlings can be grown into treasures in time. Although they might grow more slowly than some of the standard indoor trees, they are worthy of space.
If an avocado pit is grown indoors as a plant, be sure to prune it when young so that it branches and does not grow into a telephone pole. The same kind of treatment -- pruning -- is important for the jade plant. Too often these easy-to-grow plants are left to their own growing pattern and end up falling all over themselves. The jade is easy to prune with an old kitchen knife. Shape it to resemble tree form to accent the excellent branch pattern of the thick stems. Remember, too, that jade is one plant that mealybugs have a picnic on, so keep watchful eyes.
Once confidence builds up on maintaining these indoor trees, there is no limit to the possibilities. Many gardeners glean ideas from visits to the South during the winter months. If this happens, remember that most of the plants seen are growing outdoors, their natural environment, and their needs may be different when captured and grown indoors in a pot.