INCOMING! The following five awful pests will seek to utterly destroy both your garden and spirit this summer. How can you fight back against a voracious army that numbers in the tens of thousands? By reading this post and taking the advice tips from my friends at Orkin Termite Control Services.
Bad Bug #1 -- Japanese beetle (above) Brief description: Unmistakable beetle with a green thorax, green head, and copper wings. Often dines (and mates) alongside hundreds of its fellow warriors. Good work if you can get it.
Favorite targets: It's probably quicker to name what plants it doesn't eat than the ones it does. Anything in the rose family (roses, apple, crabapple, plum, etc.) and mallow family (hibiscus, hollyhock, rose-of-Sharon, cotton, etc.) are toast, but it also consumes pines, crepe myrtle, annuals, perennials, and veggies.
Damage: Devoured flowers; skeletonized foliage (everything is consumed but leaf veins). Larvae (white grubs) in ground eat lawn roots, killing grass.
Fight back with: Spray target plants according to label directions with neem oil. Don't spray flowers, though, as neem is toxic to bees. Sevin (carbaryl) is also very effective, if you don't mind "chemicals." Treat infested sod with a granular grub control applied with a spreader. Don't bother with Japanese beetle traps. They only attract more beetles to your yard.
Bad Bug #2 -- Aphid
Brief description: Aphids are small, blob like insects that suck plant juices. They can be yellow, green, orange, red, gray, or brown. Practically born pregnant, they multiply with amazing speed. The reason you see ants above is because ants "farm" aphids. They carry aphids to a host plant and drink the sweet honeydew aphids secrete. Yum.
Favorite targets: Almost any plant with juicy, green leaves and stems. They favor new, soft growth and flower buds. Often hide on leaf undersides. Don't think I've ever seen a Chinese hibiscus without aphids.
Damage: Puckered, distorted, discolored leaves; dropping leaves and flower buds; stunted growth; black mold growing on leaves covered with aphid honeydew; plants contract diseases spread by aphids.
Fight back with: Fortunately, aphids are easy to kill. Spray according to label directions with neem oil, horticultural oil, or insecticidal soap. Or fill a spray bottle with 4-5 drops of liquid detergent to a quart of water and spray aphids wherever you see them.
Bad Bug #3 -- Spider Mite
Brief description: OK, OK -- spider mites aren't true bugs that have six legs. They're arachnids, like spiders, and have eight. They're tiny -- about the size of a sharp pencil point -- and may be red, yellow, brown, or green. They suck plant juices and, like aphids, multiply amazingly fast. They usually hide on the undersides of the leaves. During severe infestations, they envelop leaves and stems with tiny webs.
Favorite targets: Almost any plant if the conditions are right. Spider mites like dry weather and low humidity. Indoor plants are spider mite candy.
Damage: The first thing you'll notice on broadleaf plants is a speckling or bronzing of the leaves. Needleleaf evergreens often brown at the branch tips. Foliage yellows or browns and drops prematurely. Branches die back. Plants lose vigor and may die.
Fight back with: Water (surprise!) Spider mites hate getting wet. So the first thing to try is blasting them to kingdom come with a strong jet of water from the hose. Wet foliage also slows their reproduction. Or use the same controls Grumpy recommends for aphids.
Bad Bug #4 -- Armored Scale
Brief description: Armored scales are weird bugs. Little scales have six legs and crawl onto the leaves and stems of target plants. There they insert feeding mouthparts into the plant to suck the juices, drop off their legs, build a protective shell over themselves to fend off predators, and remain in place until they die. Kinda like NASCAR fans. People often mistake them for harmless bumps or specks. Later, people regret this.
Favorite targets: Just about any kind of plant. Indoor plants are particularly susceptible because a scale's natural predators aren't around.
Damage: Foliage becomes spotted; growth is stunted; plant dies back; black mold grows on sweet honeydew secreted by the scales.
Fight back with: The first weapon I'd choose would be horticultural oil. Applied according to label directions, it smothers scales. Be sure to wet all upper and lower leaf surfaces, all stems, and the trunk too if it has scales. Or if you're OK with "chemicals," apply a systemic insecticide, such as Bayer Advanced 12 Month Tree & Shrub Insect Control.
Bad Bug #5 -- Brown marmorated stink bug
Brief description: About a half-inch long, this shield-shaped insect is distinguished by its banded wings and antennae. It lays clusters of 20 to 30 elliptical yellow or yellow-red eggs on the underside of leaves of target plants. A recent arrival from Asia, it builds up incredible numbers in agricultural areas. When you smash one, it stinks.
Favorite targets: Fruits and fruiting vegetables, especially tomatoes, peppers, eggplants, apples, peaches, plums, beans, corn, strawberries, figs, and citrus.
Damage: Feeding causes spotted, distorted, and dropping produce unfit for consumption. In winter, hordes of these stink bugs invade houses to avoid the cold.
Fight back with: You're not gonna like this. Most insecticides are totally ineffective against brown marmorated stink bugs. However, one natural insecticide that seems to work is spinosad. You can get this at garden centers. It's only for outdoor use. Follow label directions carefully. You can also reduce stink bug numbers by inspecting leaves for egg clusters and destroying any you find; draping target plants with floating row covers to exclude stink bugs; and knocking stink bugs into buckets filled with soapy water. To keep them out of the house in winter, carefully seal around all doors and windows.