Winter Care Of Houseplants
by Dr. Robert Black, Consumer Horticultural Specialist

Houseplants often are confronted with adverse growing conditions during the winter months. The following are key factors in keeping houseplants healthy, particularly during winter. All houseplants must have light. The best light is a southeastern exposure of filtered, never direct sunlight. Attempt to locate the plant in a permanent location, as constant moving exposes plants to changing light conditions. Too much light or direct light often causes burning of plant foliage.

Houseplants are often over-watered while a few may be under watered. Try to water, as the plant needs it. The best key to watering is to allow the top of the soil in the pot to become fairly dry prior to watering, then water well, soaking the soil. Most houseplants, depending on size of pot, location, type of soil and size of plant will need weekly waterings. A lack of water will cause yellowing and wilting of plants. However, these same symptoms are characteristic of too much water. If leaves are wilted due to lack of water, they will become turgid after a good watering. If the leaves do not become turgid after a watering, then probably too much water has been given over a period of time causing damage to the root system.

Winter heat in homes is often very hard on houseplants. The ideal temperature for most plants in the home is from 65 to 75 degrees during the day, and a 55 to 65 degree night temperature. Avoid placing plants near heat sources.

Humidity or moisture in the air is necessary and beneficial to most tropical houseplants. A 40 to 60 percent relative humidity is ideal; yet this cannot be provided in homes during winter, as heating systems dry out the air. To increase the indoor humidity from time to time, syringe the plants foliage with a fine spray of water. Another method of increasing the humidity is placing the pots on gravel, which is covered with water. Place the pots on the pebbles, being certain that the bottoms are not sitting in the water.

Houseplants must have a loose, well-drained soil. Packed soils should be loosened from time to time, being sure not to damage the root system. Plan to repot plants in spring when growing conditions are best.

Most houseplants require little fertilization during winter since rapid growth is not made at this time. Feeding once or twice during the winter months will be adequate for most plants.

Avoid drafts and provide fresh air. Plants do not like locations that expose them to cold or hot air. They also suffer from gas fumes and products of incomplete combustion, which makes fresh air essential during winter.

Clean the plant's foliage by washing with warm water. You may add a drop or two of detergent to the water used for cleaning the leaves. Rinse washed leaves with clear water to remove soap film. Keep plants attractive by removing dead leaves and faded blooms.