At this time of the year it is a good idea to check your house plants for insects. It is particularly important to do so if some of them are looking a bit unhappy.

The insects that do the most damage during the winter months are aphids (plant lice), spider mites and mealy bugs.

Where do they come from? Perhaps you brought them in yourself on your clothing. The eggs may have been there quite a while and hatched in the warmth of the home.

Aphids are small (about 1/8 to 1/4 inch in length), soft-bodied, weak-legged creatures and may be green, yellow, pink or black in color. They cluster on the undersides of leaves, or on young tender leaves and stems or flower buds.

They feed by sucking sap from the plant. The plant loses vigor, its leaves become distorted, curled and discolored, buds harden, and flowers become deformed.

Aphids reproduce at a more rapid rate than most insects.Were it not for this ability, these degenerate and defenseless creatures would be near extinction. One of the most curious features associated with aphids is the ability of females to reproduce without males.

Your best bet to get rid of aphids is to put the plants under the shower and spray them with luke-warm water. The water should wash most of them off. Assist by rubbing the leaves with your fingers or a sponge.

Spraying with an insecticide in the home with anything strong enough to be effective is impractical. It is too cold to take the plants outdoors to spray them.

Spider mites are tiny creatures, so small they can barely be seen without a magnifying glass. They are usually on the underside of the foliage where they often spin fine meshy webs.

A magnifying glass will make it easier to check the plants. Take particularly close look at plants that seem to be at all abnormal.

If the insects are present, put the plant under the shower the same as for aphids. Repeat the treatment once or twice a week for about four weeks. If this does not get rid of them entirely, at least it will reduce the population to the point that little or no damage will be done.

Mealy bugs are coated with a cotony white covering. They usually are found on the stems where the stems and leaves join, and on the undersides of leaves. A good treatment for mealy bugs is to dip pad cotton in rubbing alcohol and wipe the bugs off with it.

"The alcohol will kill the bugs without damaging the plant.

If mealy bugs are present, the plants should be inspected and treated once or twice a week for four or five weeks. They will continue to hatch from eggs for a long time.

Most house plants should have their leaves cleaned once a month. It is particularly desirable for foliage plants such as the split lead philodendron, rubber plant, dieffenbachia and schefflera.

Use a sponge and water at room temperature with a small amount of very mild soap added (not a detergent).

Washing the leaves accomplishes two things. It opens up the pores and helps keep insects from building up to a dangerous level.

Plants breathe through their leaves. Nicotine from a heavy smokers or dust can cause a film to form on the leaves and clog the pores.

Handle the leaves gently. Rough treatment may cause the edges to turn brown.

A good shine can be achieved by rubbing the foliage gently with soft cheesecloth or a fine camel's hair brush.

The natural oils in the leaves should produce a high gloss. If they don't, try ordinary milk. It contains just enough fat to shine green leaves.