Joseph Masabni, Assistant Professor and Extension Horticulturist; and Patrick Lillard, Extension Assistant, The Texas A&M University System
Many kinds of insects feed on garden plants. Insect pests damage plants in two ways. Some chew holes in the leaves, stems, roots or fruit, and some stick their beaks into the plants and suck out plant juices.
Insects attack garden plants at all times of the year. Some insects will feed on sprouting seed and young seedlings. Others feed on the growing plant or on the mature plant and its fruit.
Kinds of insects
The insects that feed on garden plants can be divided into two main groups: the sucking and the chewing insects. These are some of the most common insect pests and the damage they cause.
Recognizing insect problems
A good gardener must learn to recognize insect problems. To know when insects are damaging your plants, watch for anything that does not look normal.
The following symptoms will help you recognize insect problems.
- Plants are stunted and do not grow properly.
- Plants have deformed or damaged leaves.
- Plants look yellow or light in color.
- Plants look wilted and droopy If your plants show any of these symptoms, examine each plant closely for insects. Also examine the soil near the plant base, as many insects drop and hide there when disturbed.
Controlling insects
Many insects can be managed without using pesticides, but this cultural control requires extra time and effort. It may also result in slight damage to your plants. Some of the cultural methods you can use to prevent or control insect damage are:
- Keep weeds and grass pulled out of the garden. Mow the area around the garden.
- Plant varieties that grow well in your area.
- Apply the correct amount of fertilizer and water when needed.
- When you have picked all the fruit, destroy the old plants by removing them or plowing them under.
- You can wash off some insects, such as aphids and spider mites, with a water hose.
- You may hand-pick some insects or egg masses from the plant to prevent damage.
- Chemical control of insects often may be necessary. For best results, treat insects before large numbers build up in the garden. Dusts or sprays provide good control.
Before you buy a pesticide, read the label to see if it is recommended for the pest and plants you want to treat. Before you use a pesticide, read the label to see how much you should use. Read all information on the label and follow all directions.
All insecticides are poisonous, so handle them with care and keep them away from children and pets.
Some insecticides recommended for home vegetable gardens:
Download a printer-friendly version of this page: Insect Control (pdf)
View this publication in Spanish: Control de Insectos
Purchase this book: Easy Gardening in Texas