Wikipedia defines aphids as “plant lice, young white flies, green flies and black flies” and names them the most destructive insect pest in temperate regions. They are probably the most common of all the insects you will find in a yard or garden and the problem with them is that their palette is not discerning. They eat just about any type of garden plant—flowers, trees, shrubs, and vegetables. What they eat is the sap or juice in the plant. They love tender young shoots because these are easier to suck the sap out of, but of course this weakens the plant and makes it unsightly.
Choosing aphid control and treatment isn’t as simple as picking something up off of a store shelf. You can choose the right treatment by calling your landscaping and plant professional. Depending on which plants or shrubs your aphids are attacking—where you live—and how close your plants and shrubs are to people, pets and other life – will all affect the right choice for you. There are an enormous number of sprays and powders but most of them have at least some detrimental effect on wildlife—birds that eat insects can be affected and of course beneficial insects can be killed as well. Especially with vegetables and edible plants you must be choosy with pest control products.
Your landscaping professional will determine if one or multiple treatments will be necessary to correct your aphid problem. They are trained in use of pesticides and will use one or a combination of these products below.
Some people follow recipes for homemade sprays that contain various oils and soaps and even garlic. These can work with moderate results, but usually aren’t effective long term. And they must be applied frequently. Your landscaping professional can recommend a commercially produced non-chemical insect control spray and apply it for you correctly. Potassium salt soap is a common ingredient in both homemade and commercially sold insecticide sprays. Vegetable friendly dusting powder is commonly used also.
There are many insecticide sprays used by landscapers, with varying degrees of chemicals and ingredients that could potentially harm other bugs, mice, lizards, birds etc. If you don’t have any other wildlife in your garden or lawn then these are more of an option for you. They are a bit more effective and work faster than homemade or organic aphid remedies.
Aphids do have enemies. You can actually place other plants that draw these enemies near your plants that are being attacked by aphids and this will significantly reduce the number of aphids you have. Morning glory, calendula, and poached eggplant are examples of plants that will draw other bugs that eat aphids. These include ladybirds, lace wings, and hover flies. Hover flies actually lay eggs that, when hatched, the larvae produced feeds on the aphids and this really works. Nettles are a good plant to have near your aphid plants as well because they attract the nettle aphids which the aphid enemy bugs feed on. But the nettle aphids wont attack your other plants. This ensures that even when your bad aphid population goes down the aphid’s enemy insects will stick around, keeping the population from coming back again.
Your garden and lawn are natural homes for insects. When you’re out watering, a steady hard stream from your garden hose is a quick easy way to annihilate some of your aphids and other plant eating insects until the next visit from your landscape expert. Having them determine the best products and methods ensures that you’ll find something that works, and that you are comfortable using.