Wednesday, April 4, 2007

Controlling Aphids

Aphids are tiny insects (1/32 to 1/8 of an inch) that have piercing/sucking mouth parts. They infest tender new foliage on both annual and permanent plants, usually in spring or early summer. Aphids ingest the fluids from tender leaf or stem tissue of the plant, robbing it of nutrients. Aphids also spread disease by moving from one plant to another. Even without resorting to chemical methods, they're not difficult to get rid of.

STEP 1: Look for aphids on the undersides of leaves and on tender new growth. You will notice a yellowing of the leaves on new growth, most often in the spring or early summer months. Aphids are usually found in large colonies, called infestations.
STEP 2: Spray a strong jet of water directly onto the affected area of the plant. The stream will wash the insects off. This is the easiest way to control aphids.
STEP 3: Spray with a soap/oil mixture if the water alone doesn't do the job. Mix 1 tsp. insecticidal soap with 1/2 tsp. horticultural oil in 1 quart water in a spray bottle. There are also numerous chemical sprays available.
STEP 4: Try ladybugs for serious aphid infestations. Place a newly purchased bag of ladybugs in the vegetable crisper of your refrigerator while you go outside and water your garden. Release them during the evening hours to protect them from hungry birds.
STEP 5: Attract other types of predatory insects that will consume and control aphids by planting dill, fennel, coreopsis and brightly colored flowers near the aphid-prone plants.
STEP 6: As a preventive measure, spray during the dormant season (winter) to head off severe recurring infestations - aphid eggs overwinter on woody stems. Use a dormant-season oil spray.

Tips & Warnings

Always try the least toxic method of pest control as your first step.
Water your garden prior to releasing ladybugs. They are thirsty from traveling and will eat aphids after taking a refreshing drink.
Select and grow plants that are naturally resistant to aphids. These include plants with a milky sap and thick or fuzzy leaves; the particular plants will vary depending on where you live.
Plants native to your area are generally naturally resistant to insect attack. Hummingbirds eat aphids too! Encourage them to visit your garden by hanging a feeder and keeping it clean and full.
If you use pesticides in your garden, you will kill natural predators of aphids such as ladybugs and lacewings.
If you choose a chemical control, always wear protective clothing and safety gear, including a long-sleeved shirt, long pants, neoprene gloves, goggles and a respirator.

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