Plants cheer up dark corners

The darkest days are upon us, making the darkest rooms that much darker. Let's cheer up those dark rooms with living plants and let's avoid using artificial lights in the process. Artificial light is of limited use, either because plants must be set within just a few inches of them or because they cast an eerie glow over plants and furniture. In either case, darkness might be more hospitable.

Artificial lighting does have its place in indoor gardening, but let's put it aside for now. There are plants that survive long periods in dim light.

Before going any further, let's determine what we mean by "dim." The traditional measure of light is the foot-candle, the amount of light illuminating a surface one foot from a candle. For comparison, on a sunny, summer day your garden outdoors is bathed in 10,000 foot-candles, while only about 500 foot-candles peek through an overcast winter sky.

Drop that figure to 25 to 100 foot-candles for a dimly lit corner inside a room.

We must look to the depths of tropical jungles to find plants able to survive these conditions. Tropical jungles are dense with greenery, with light intercepted by tree canopies, by vines clambering up the trees and by shrubby vegetation nearer the ground. The needed plants are those found at ground level, perhaps also nestled into the crotches of large tree limbs. They include maidenhair and birds nest ferns, as well as numerous palms, including the lady, parlor, kentia, and bamboo palms. Vining plants also: philodendron, Swedish ivy and grape ivy, the former Scandinavian only in name and the latter only distantly related to grapes.

Indoors, winter "weather" is dry as well as dark, and the drier and darker it is, the tougher the plants needed. Some of the plants that are most tolerant of low light and dry air are dracaena, also known as corn plant, Chinese evergreen and the aptly named cast iron plant.

Although they're tough, any of these plants would appreciate a light-filled vacation once a year, or at least every two years. Summer seems most appropriate, because that's when we also are more often outdoors, so the plants will not be missed from their dark corners. Much as these plants hunger for more light, after months of darkness they can tolerate low doses only. A few months in dappled shade is more than enough to recharge them for more dark days in dark rooms ahead.