GIMME SHELTER- Aphid attack! Act now to save your plants
Virginia Cooperative Extension, Agriculture & Natural Resources
Q: I have some young plants I am planning to put my garden, but now I see they are infested with aphids. What should I do?
A: Some plants can tolerate populations of aphids without sustaining any direct damage from the feeding itself. This can be good news as long as the plants are not susceptible to some disease the aphids may transmit. At higher populations, aphid colonies can consume so much plant fluid that leaf curling or distortion may occur.
Indoors, aphids can be managed with insecticidal soap. To keep them under control, try the following tactics:
• Carefully inspect any plant you plan to purchase or propagate for evidence of pests.
• Buy or propagate only pest-free plants.
• Isolate new plants from the vicinity of existing plants for at least a month and look for evidence of pests before placing them among clean, healthy plants.
• Remove and isolate any existing plant at the first suspicion of pest infestation.
• Avoid placing plants close together to discourage pests from crawling from plant to plant.
• Never permit compassion for a sick plant to justify bringing home diseased, pest-ridden plants to recover and (in your dreams) become beautiful again.
• Use clean pots, potting materials, and soil mix components.
• Use only sterilized soils or soil mixes.
• Do not contaminate potting soil or pots with garden soil, compost, old soil from used pots, or cuttings from infested plants.
• Select plant varieties known to be resistant or relatively free from attack.
Outdoors, aphids can be controlled by beneficial insects, spiders, fungi, and other natural control agents throughout most of the season. Using a broad-spectrum insecticide can kill many of these beneficial insects, spiders, and fungi and allow aphid populations to increase rapidly.
To monitor for aphids, check the underside of leaves each week. When you monitor the population and record the data each week, it's easy to see if populations are increasing, decreasing, or remaining relatively stable over time. You also learn to identify important predators and parasites during this process and begin to realize how plentiful beneficial insects really are.
If you use insecticides, try to alternate between chemical families when spraying to avoid selecting for the survival of resistant individuals. Use insecticides only if there's an existing problem. Continuous preventive use of insecticides will eventually result in resistant populations.
FILE PHOTO BY DAVE MCNAIR