If you follow good organic gardening practices you may not have serious problems with tomato bugs. Usually diseases are more of a problem than insects. But insects frequently spread tomato plant diseases as well as cause their own destruction so it's still important to control them.
Keep reading for a list of most of the common tomato plant pests along with some suggested organic garden pest control solutions.
With luck one of the suggested organic garden pest control methods will work for you. These solutions are environmentally friendly and should be tried first. If you need stronger action such as pesticides, you should consult a knowledgeable expert at your garden center, contact your county agricultural extension office, or your local Master Gardener organization for a referral.
Good for controlling many sucking and chewing bugs including aphids, leafhoppers, and whiteflies. Soak 3 ounces of finely chopped garlic in 2 teaspoons of mineral oil overnight. Add 1 tsp. of insecticidal soap to 2 cups water and mix in the garlic oil. Strain the mixture. Store this as your concentrate in a glass container. Add 2 tbsp. of the base to 2 cups of water and spray on the insects.
By following these basic practices you can raise the odds of having strong healthy tomato plants which will help prevent problems with tomato bugs:
Symptoms and signs: Colonies of small (less than 1/8-in.) green insects found on new stems and undersides of leaves
Treatment: A strong stream of water can wash off insects. You can encourage natural predators like ladybugs or lacewings. Also effective for many tomato bugs is the use of repellant garlic oil spray
Symptoms and signs: Medium size (3/4-in.) black, red, gray, or striped adult beetles chew on leaves. Large numbers of them can defoliate the plant rapidly before moving on. You may see dark fecal spots on leaves and stems.
Treatment: Blister beetles beneficial aspect is their diet of grasshopper eggs. To eliminate handpick and dispose (use gloves, they can blister your skin with their secretion of canthara-dine, but most of those found in gardens have relatively low amounts so aren't much of a threat). Drop into soapy water to kill them -- this works for most tomato bugs.
Symptoms and signs: Smooth one-inch caterpillars found curled in a C-shape in the soil feed at or just below soil level. They can cut off young plants evenly at the surface of the soil. Colors vary from gray, black, brownish, to green.
Controls: 1) Cutworm collars: put a collar around seedlings made from bottomless paper cups or 2-inches of a toilet paper tube. Push the tube into the soil. Shallow tin cans with bottoms removed also work. 2) Scatter bloodmeal around the plants. 3) Scatter moth balls around the plants. 4) Dig up the garden in early spring to expose and kill cutworms by freezing or starvation.
Symptoms and signs: One- to two-inch black insects with a pincer-like tail damage the leaves of young tomato plants.
Controls: 1) Lay boards on the soil then destroy the earwigs that congregate overnight. 2) Let your chickens make a meal of them. 3) Make an earwig trap by rolling up a single sheet of newspaper into a cylinder and securing it with tape or rubber bands. Dampen the paper, lay it in the garden overnight. Earwigs will hide in the paper; dispose of it in the morning.
Symptoms and signs: Small (1/8-in.) dark brown metallic-colored jumping beetles make tiny "shot-holes" in leaves. The damage can stunt or kill small plants
Controls: Keep weeds under control where the flea beetles nest (a good practice for controlling many tomato bugs). Plant basil nearby, which repels them. Sprinkle plants with an insecticidal soap solution.
Symptoms and signs: medium size (1/2-in.) shiny green/bronze beetles feed on foliage until the leaves are skeletonized and appear lacelike. The white grub larvae is one of the most damaging to grass lawns in the northeastern U.S.
Controls: Hand pick or use milky spore insecticides to kill the grubs. This does not kill the beetles however.
Symptoms and signs: Small (1/8-in.) wedge-shaped pale-green/tan hopping insects which feed on sap and cause curled leaves with dark tips. They rarely cause significant damage but they can transmit plant pathogens that cause plant diseases such as curly top.
Controls: Blast with water spray (in the mornings so leaves dry by nightfall). Cover plants with floating row covers. Spray with insecticidal soap or other organic pesticides or dust with sulfur. Avoid planting tomatoes near beets.
Symptoms and signs: Includes tomato erinose and spider mites. Mites are tiny insects that cause the leaves to look like they're covered with a white mold because of the webbing they produce. They attack leaf tips and blossom buds. They puncture leaves and feed on the sap.
Controls: Avoid dry, dusty conditions by having a consistent tomato watering program. Also avoid nitrogen fertilization. Predator mites are an effective control. Prune and discard heavily infested branches. Wash off with a mild detergent and water rinse.
Symptoms and signs: These are microscopic wormlike creatures; the best known is the root-knot nematode. They cause yellow foliage, wilting, and stunted plants; they can be diagnosed by observing irregular swellings on roots.
Controls: Nematodes are easily spread by garden tools and soil on gardener's boots. Sanitize by removing and destroying all infested plants after harvest. Sterilize tools at a minimum with soap and water. Don't add affected plants to compost pile. Remove as much of the root system as possible, including much of the surrounding soil. Clean pots with 10% bleach/water solution before reusing. Grow nematode resistant tomato varieties which will have and "N" listed after the plant name. An effective soil treatment for these tomato bugs is to grow marigolds to maturity then plow under -- nematodes can't tolerate the chemicals released.
Symptoms and signs: Also known as potato beetles. They are small 1/2-in. yellow and black striped beetles that feed on tomato plant leaves.
Controls: Handpick off plants or knock off into a jar of soapy water to destroy. Avoid planting tomatoes near potatoes. Dust with Rotenone.
Symptoms and signs: Slimy, dark soft-bodied creatures up to 4-in. long feed at night and on cloudy, damp days. They feast on tomato foliage and fruit on or near the soil surface. Both slugs and snails lay masses of white, oval to round eggs.
Controls: 1) Handpick daily, then weekly, when their numbers decrease. 2) You can make a trap from a 1-ft. square board with 1-in. x 1-in. runners on the four sides. Snails and slugs will congregate underneath where they can be disposed of in the morning. 3) Place shallow pans of beer near plants. The slugs will crawl in and drown. An alternative to beer is one tablespoon of flour and 1/8 teaspoon of yeast mixed with a cup of water. 4) Mulching your tomato plants with coarse mulches like hay or placing rough rocks around the plant stems will also discourage slugs. 5) Commercial baits like Slug-Geta can also be effective.
Symptoms signs, and controls: See the previous notes on Slugs.
Symptoms and signs: While not one of the most damaging tomato bugs, stink bugs pierce fruit and cause dimpling and sunken spots on fruit.
Controls: Since they congregate on weeds, the best control is to keep the garden weeded and handpick insects when found. Drop into soapy water to kill them.
Symptoms and signs: Also known as the corn earworm and cotton bollworm. Two-inch yellow to gray worms with lengthwise stripes tunnel into fruit. They also feed on tomato leaves. Brown pupae are about 3/4-in. long and found three to four inches deep in the soil. The fruitworm moth lays eggs on the leaves; the eggs are white at first then develop a brown ring.
Controls: Handpicking of the larvae or eggs is one control. Another is to till the soil in the fall which exposes the pupae to predators and cold. Bacillus thuringiensis, Rotenone and garlic sprays are effective chemical controls.
Symptoms, signs and controls: Read detailed information about hornworms in the article Tomato Worms - Tobacco and Tomato Hornworms.
Symptoms and signs: Chiefly a greenhouse and houseplant pest in the northern hemisphere. They are tiny yellowish insects with white wings which cause damage to leaves by feeding, which causes leaves to yellow and curl. Usually rest on the underside of leaves. They are active flyers and move from plant to plant.
Controls: Spray foliage with water (early in the day so it can dry before evening) to disrupt feeding and dislodge eggs, nymphs and pupae of the whitefly. Lowered temperatures also decreases activity. A small wasp, the encarsia formosa, which is available from suppliers, is a natural predator that can be introduced into the environment to control the whitefly population.
Symptoms and signs: These light brown hard-bodied 1/2-in. to 1-1/2-in. worms are the larval stage of the click beetle, which gets its name from the sound they make when they flip over when laid on their back. They feed on underground stems and small roots, causing stunting of plants and reduced yields.
Controls: Tilling the soil frequently kills wireworms or exposes them to predators such as birds. Apply beneficial nematodes. Rotate crops by not planting in the same spot each year.