Give houseplants TLC in winter

Last Updated: 
December 12, 2008

CORVALLIS, Ore. - Now that winter is on the way, there's more time to pay attention to your houseplants. The most important factor in the care of houseplants is matching up a plant's needs to its environment, explained Ross Penhallegon, horticulturist with the Oregon State University Extension Service.

Avoid placing plants near direct sources of hot or cold drafts. A sudden change of temperature from doors, windows, furnace ducts, candles, wood stoves or television sets can be detrimental to a plant. Wilting foliage and brown tipped leaves may be symptoms of a temperature problem.

Fertilize lightly during the active growing season to keep houseplants healthy. Use a water-soluble medium strength fertilizer (10-5-5) and apply monthly during the spring and summer. During the winter, fertilize lightly every other month to keep the foliage green.

Over-watering is the most common problem with houseplants, said Penhallegon. Water each plant according to its needs, rather than by a regular schedule. Plants in containers with drainage holes can be thoroughly watered, as the excess drains out. If there are no drainage holes, check soil two inches beneath the surface by sticking your finger into the soil to detect whether the soil is still damp before adding more water. Plants without drain holes will often have yellowing lower leaves and will gradually decline. Too much water encourages root rot. Move plants to better drained pots if you suspect inadequate drainage.

Insect pests can move in unexpectedly. Check the undersides of leaves regularly, especially on those plants brought in from outdoors. Wash the foliage regularly with a mild soapy solution, taking care to rinse all soap off completely. A fine water spray or wiping the leaves with alcohol-soaked cotton will take care of most insects. Rinse off all the alcohol. Use any chemical insecticide with great care.

Light source, light intensity, temperature and total room environment are all crucial to houseplants. Each plant has its own individual cultural requirements, but will tolerate some changes. But once a houseplant is happy, try not to move it much.

All plants require some natural light. Generally, flowering plants prefer stronger light; foliage plants will tolerate very low light conditions. On the whole, it is best to avoid hot direct sun rays for long periods of time. A bleached out area on a plant's leaves indicates too much light. Thin, leggy growth in a plant means not enough light.

Author: Carol Savonen