If you moved your houseplants outdoors last spring, this is the week to bring them in before the first frost.
But first you had better inspect them for bugs. One of the major problems associated with moving houseplants outdoors in warm weather is that they become exposed to a greater variety of insects generally not found indoors.
Examine the stems, tops and underside of leaves and flowers closely for both insects and egg masses. The most common insects are spider mites, aphids, spittlebugs, mealy bugs and scales.
Spider mites make fine webs in the axils of leaves and stems or in flower clusters. If you see no webs, it is best to test for their presence by placing the plant on its side over a white sheet of paper and gently taping the stems and flowers. If you see little red or green dots moving on the paper, the plants are infested. In that case, thoroughly spray the foliage with a two percent solution of horticultural oil, a very safe method of organic pest control. After the oil has dried, the plants can be brought indoors.
Aphids generally appear in clusters near the growing tips of the branches, on the backside of leaves or in the axils of leaves and stems. They are roughly the size of a pinhead and may be red or green. Control them with a good application of insecticidal soap. Turning the plant upside down and dunking the top in a pail filled with the insecticidal soap solution is the simplest and fastest method of treating many plants infested with aphids or for general care.
Spittlebugs generally appear in the axils of leaves and stems as small globs of spit. Lay the plant on its side on the lawn and blast it with a strong stream of water from a garden hose as you role it on the grass so that you get all sides. Follow with a treatment of insecticidal soap.
Mealy bugs appear as small globs of oatmeal on the stems and on the petiole of leaves. Control these insects as you would spittlebugs.
Soft scale insects most commonly appear on the stems and leaf petiole of foliage plants. Look for a chocolate-brown to light-brown bump tightly clinging to the stems or petioles. Scrape them off with your fingernail, making certain that the scales are not falling on the surface of the potting soil. After you have removed all that you can find, spray the plant thoroughly with a three percent solution of horticultural oil. Allow the foliage to dry before bringing the plant indoors.
Look for egg masses on the stems and under the leaves of plants. Insect egg masses are generally creamy yellow to chocolate brown in color. Most can be removed easily by brushing them off with an old toothbrush.