The best way to keep ahead of pests is to inspect the garden frequently and regularly. That way pests can be observed and controlled before much damage is done.
Aphids are short, soft-bodied insects about 1/8 inch long which are most commonly light green in color, although, brown, red and black ones are also seen. Aphids suck sap from plant tissues causing foliage and blossoms to wilt and shrivel. Severely injured plants turn yellow, dry up and die. Aphids are also known to transmit diseases from sick to healthy plants. Small populations are often controlled by predators such as the Lady Bird Beetle or washing them off with a hose nozzle. Insecticidal Soap is effective in removing aphids from plants. Apply pesticides containing Neem Oil, Paraffinic Oil, Carbaryl, Acephate, Cyfluthrin, Malathion or Pyrethrum to control large colonies which are causing plant damage. Repeat treatments may be required.
Beetles are hard shelled oval insects which chew holes in the leaves. Beetle grubs can also damage plant roots. Control with dusts or sprays containing Neem Oil, Carbaryl, Acephate, Cyfluthrin, Malathion or Rotenone. Several treatments may be necessary.
Caterpillars or worms are the larvae of butterflies and moths. The moths lay white eggs on the underside of the leaves. The worms vary in color from green to black and some have hairs or bristles. As soon as caterpillars are noticed, spray with Bacillus thuringensis, Neem Oil, Acephate, Carbaryl (Sevin), Cyfluthrin, Spinosad, or Malathion. Spraying may need to be repeated.
Cutworms are generally smooth, shiny and gray to black in color and are usually found under the soil surface during the day. They feed mostly at night and will attack nearly all plants. Surface cutworms feed on plants near the soil surface. Climbing cutworms crawl up plant stems to feed on foliage. Subterranean cutworms remain under the soil surface and feed on underground portions of plants. Thorough treatments with Carbaryl (Sevin) dusts or sprays applied to the ground surface, especially around young plants, is effective. Carbaryl bait is also quite effective. Light populations can be hand picked at night with the aid of a flashlight.
Grasshoppers eat the leaves of many different flower plants. They have enormous appetites and a large population can quickly defoliate a garden. Sprays containing Carbaryl, Acephate and Rotenone are effective in controlling grasshoppers. Baits are sometimes also available.
Leafhoppers are small flying insects which cause white spots on the leaf surface of plants where they feed by sucking plant juices. Damage from direct feeding is light, but they also transmit virus and related diseases. They can be controlled by applying pesticides containing Neem Oil, Carbaryl, Acephate, Cyfluthrin, or Malathion. Control is seldom necessary except to prevent disease spread.
Leafminers attack certain flowers. Adults are small gray flies which deposit eggs on the leaf surface. A white to yellowish maggot hatches, feeds on the tissue between the upper and lower leaf surfaces and makes long, winding mines or blisters. Control by spraying or dusting with pesticides containing Acephate, Spinosad or Cyfluthrin when damage is first noticed.
Mites are tiny, spider shaped pests which are only 1/50 inch long and barely visible without magnification. The most common is yellow or light green with two dark spots on the back. They suck juices from the under sides of leaves and cause them to turn light green, mottled and speckled. Early infestations can be controlled by washing the foliage with a hose nozzle. Insecticidal Soap is effective in removing mites from plants. It is important to direct the spray to the bottoms of the leaves. It requires 3 applications at 7 to 10 day intervals to control newly hatching mite eggs. Products containing Neem Oil, Paraffinic Oil, Kelthane, or Acephate are effective against mites.
Slugs and Snails are slimy, legless pests varying in color from white to black. Predominant color is gray or brownish gray. They spend the winter in the soil as eggs. They appear in early spring and attack tender seedling plants. If large numbers are present, they can completely destroy newly emerged seedlings or young transplants. They feed at night and hide in the soil or under trash during the daytime. They are most effectively controlled by baits containing Metaldehyde or Iron Phosphate. Baits should be scattered on the soil around plants. They should be moistened after scattering. Iron Phosphate baits can be used safely around pets. After a few days the bait loses its effectiveness and new bait must be applied.
Earwigs are nuisance pests which grow to about 3/4 inch long. Their bodies are reddish-brown with legs, antennae and wing covers a yellowish-brown. A pair of forceps is on the rear of the body. Earwigs feed at night on the tender portions of plants such as flowers. Earwig and Cutworm baits containing Carbaryl are the most effective. Dusts or sprays of Carbaryl can also be applied as a protective border around affected plants.