In our last post, “Ladybugs Feast on the Most Common Garden Pests: Aphids” we discussed one of nature’s ways to control aphids – the mighty ladybug. There are also a few other ways that you can mitigate aphid propagation.
1) Examine Your Plants then Prune or Blast with Water
Word on the street is that a single little aphid can produce 80 baby aphids a week! It’s important to carefully examine your plants weekly for the little buggers.
They live on the underside of leaves and tend to be found in groups or colonies. If you find them, you can blast them with water, collect and squish them while wearing your favorite garden gloves, or clip off the branch or shoot where they have congregated. These methods are effective with a mild aphid gathering.
2) Over Fertilization
Be careful not to over fertilize your garden. Since the aphid preys upon the youngest parts of a plant, fertilizers can cause an abundance of new growth. If you do fertilize then it’s best to use fertilizers that release slowly over time.
3) Dish Soap to the Rescue!
Another effective method is to use ordinary household dish soap or mild laundry detergent which destroys the aphid’s waxy coating on their bodies causing dehydration. Mix two teaspoons of the soap or detergent into a spray bottle of lukewarm water and spray the leaves once a week.
4) Avoid Plants that Aphids Love
Birch trees are known to attract aphids, so don’t plant your garden near one. A better plan is to plant Queen Anne’s lace, spearmint, or fennel because these are known to attract aphid predators such as ladybugs and lacewings.
1/2) Commercial Aphid Insecticides
If all else fails, you can use some commercial insecticides to kill the buggers. Gardeners use insect growth regulators (IGRs), pyretherins, and/or insecticidal soaps. IGRs work in different ways to kill aphids. Some mimic juvenile hormones which prevents the aphid from reproducing. Other IGRs interfere with the production of “chitin” which causes problems with exoskeleton formation. Pytherins are extracted from chrysanthemums and they attack the nervous systems of insects. Finally, insecticidal soap sprays can suffocate the aphid by washing away its protective waxy coating, or the soap sprays can hinder the permeability of the cell membranes. Any of these insecticide types will help dramatically reduce your aphid population.
This post is by Justin Rickard, a writer living on the Front Range of Colorado.