What are aphids?
They are soft-bodied insects that suck the sap from the plant leaves or roots. They are commonly found on trees, shrubs and flowers. Aphids come in many different colours such as green, yellow, brown, pink or black and sizes. Aphids excrete a sugary substance called honeydew on the leaves which overtime can cause sooty mold. In most cases aphids are found in the folded over part of leaves, known as a clutch. This is where the eggs and the next generation of new nymphs are present.
How can I control aphids?
You can control aphids on trees, shrubs and flowers by frequently hosing plants with high water pressure. Hosing your plants knocks most of these insects off and kills many of them. It may require several treatments to reduce the population.
If you have a severe aphid infestation, mix one to two tablespoons of 100% pure dishwashing soap (not regular dish soap) to one gallon of water. Spray this mixture in the early morning or late evening and rinse the plant thoroughly the next morning. Some plants may be sensitive to the soap and cause the leaves to have a chemical burn. Test on a small area first before treating the entire plant. You can also purchase an Insecticidal Soap from home and garden centres.
We do not recommend using chemical insecticides for aphid control because the aphid population will rebound to the same level in about a week. Insecticides such as Malathion® can be used occasionally. Make sure to follow label directions. All Pest Control products purchased and used must be registered with Health Canada and contain a Pest Control Product (P.C.P. or PCP) Number on their label.