Eco Friendly Aphid Control

Aphids are one of the most easily recognizable garden pests. While they are usually thought of in relation to roses, they attack many other species. Aphids can cause damage by spreading disease or sucking up a plant's sap. If you only see a few in your garden, don't worry - aphids are only a problem in large numbers. On the other hand, if you feel like your garden is being taken over, it's time to take some steps to control the infestation. It's easy to be tempted by conventional insect control methods when dealing with aphids. They are tiny and they are legion, making it seem overwhelming to fight them off using organic methods. Never fear - you too can get rid of your aphid problem without harming the environment or driving yourself crazy. For all you environmentally-minded gardeners out there, here are some eco-friendly options for keeping the aphids away.

One of the better known methods of aphid control is the ladybug. While they voracious aphid-eaters, buying ladybugs isn't the best way to solve your aphid problem. While it might look like there are a lot of aphids in your garden, unless you have a few acres of aphid infestation, your newly bought bugs will fly away within the day in search of better eats. This will leave you at square one once the aphid population bounces back. In any case, the very presence of aphids will be enough to attract predators looking for food.

The most effective aphid control measures are the simplest. If you only have a few plants affected by aphids, just squish them by hand. If the problem affects too many plants to make that an efficient control method, you can also spray the aphids off the plants with a hose. The only precaution you need to take is to make sure that the plants are large enough to hold up against the spray.

Spraying plants with oil will also control the aphid problem. You can use vegetable oil - cottonseed and soybean oil are the most effective at controlling pests. There are also special horticultural oils that can be found at some nurseries. Many commercial horticultural oils are petroleum based, so use your judgement on this one. You can also spray with neem oil, which is made from the seeds of the neem tree. Though all the oils above are basically nontoxic, they can damage seedlings and the mature plants of some species. Talk to your local nursery about proper application and use of horticultural oils.

Companion planting is a very effective and low maintenance way of controlling your resident aphid population. Not all plants are vulnerable to aphids; in fact, aphids are repelled by the scent of chives and nasturtiums. Plant some around your garden, or just near your most aphid-vulnerable plants to drive the little pests away. Another way to use your companion plants to keep aphids away is to use them in an all-natural spray. Combine nasturtium leaves and water in a one to one ratio and bring the mixture to a boil over the span of fifteen minutes. Once it cools, strain the mixture and use it as a spray.

There are other spray recipes you can try. You can use rhubarb in much the same way as the previous herbal spray used nasturtiums: combine one part rhubarb with four parts water, boil, let cool and then strain. The simplest recipe is just soapy water - mix a little dish soap (preferably the organic kind!) with water and spray it on the affected plants.

A variation on the soapy water recipe from GardeningKnowHow.com adds in vegetable oil for a one-two aphid punch: mix one cup of vegetable oil, one and half cups of water, two tablespoons of dish soap and spray. A second soapy water recipe variation from ThriftyFun.com combines two cloves of garlic, a small onion finely chopped, one tablespoon of dish soap, and two cups of water. This mixture combines the insecticidal effectiveness of soapy water with the insect-repellent qualities of strong smelling roots like garlic and onion.

Pyrethrum should be considered a last ditch and only relatively eco-friendly aphid control option. Pyrethrum is derived from chrysanthemum flowers, and works by affecting an insect's nervous system. Pyrethrum is one of the least poisonous insecticides to mammals, though it is highly toxic to fish, tadpoles, and beneficial insects (1). It also breaks down quickly in soil and water and when exposed to sunlight. While it is possibly the best insecticide option, it is still a relatively toxic chemical and should only be used selectively when an aphid problem is severe.

1) http://npic.orst.edu/factsheets/pyrethrins.pdf