Your garden is a natural home for insects — a home where the
door is always open. And although you may worry when you spot
bugs on your prized vegetables or flowers, the fact is that many
insects aren’t bad guys at all! They may be in your garden to
pollinate flowers or even to prey on plant pests. And most garden
plants are a lot tougher than we might think. They can tolerate
some insect damage and still produce lovely flowers or a good crop,
which is one reason why spraying pesticides isn’t necessary.
Of course, not using pesticides doesn’t mean you just sit back and
let the bad guys go to town in your gardens. But if you use
organic techniques, such as these for aphids, cabbage loopers,
cutworms, Japanese beetles, and thrips, you’ll be battling
destructive insects without harming beneficials, the environment,
or you and your family.
Aphids are soft, pear-shaped, and very tiny (1/16 to 3/8 inch long). Two short tubes project backward from the tip of their abdomen. Aphids have long antennae. Some types of aphids have wings, which are transparent, longer than their body, and held like a roof over their back. Aphids may be green, pink, yellowish, black, or powdery gray. Nymphs resemble adults but are smaller and wingless.
* Drench plants with strong sprays of water from a garden hose to kill aphids.
* Keep your plants as healthy as possible, and spray dormant oilto control overwintering eggs on fruit trees.
Cabbage looper adults are mottled gray-brown moths with a silvery, V-shaped spot in the middle of each forewing. Their wingspan is 1 ½ inches. Because they fly late in the evening, you rarely see them. Their larvae are green caterpillars with pairs of wavy, white or light yellow lines down their backs and one line along each side.
* Handpick caterpillars several times a week.
* Attract predatory and parasitic insects to the garden with pollen and nectar plants.
* At the end of the season, bury spent cabbage plants to destroy cocoons before adults emerge in the spring.
Adult cultworms are large, brownish or gray moths with 1 1/2 – inch wingspans. The larvae (which do the damage) are fat, grasy gray or dull brown caterpillars with shiny heads.
* Protect transplants by putting collars around the stems. Press the collars about 1 inch into the soil.
* Avoid the main population of cutworms by planting later in the season.
Japanese beetle adults are blocky, metallic blue-green beetles ½ inch long. They have bronze-colored wing covers and their legs are relatively long, with large claws. Beetle larvae are fat, dirty white, C-shaped grubs with brown heads, up to ¾ inch long.
* In the early morning, handpick beetles or shake them from plants onto sheets, and then drown them in a bucket of soapy water.
* Aerate the lawn with spiked sandals to kill grubs while they’re close to the soil surface in late spring and early fall.
Adult thrips are minute — about 1/50 to 1/25 inc long. They’re yellowish brown or black and have narrow, fringed wings. They move quickly and like to hide in tight crevices in plant stems and flowers. Nyupmphs are light green or yellow and look similar to adults, but smaller.
* Spray dormant oil in early spring to control thrips attacking fruit trees.
* Use bright blue or yellow sticky traps to catch adults in greenhouses.
* Wash thrips off with a strong spray of water from your garden hose.