What permanently eliminates aphid infestations?
Written by
Paul Reynolds
Reviewed by
Prof. Samuel Fitzgerald, Ph.D.Permanently eliminating aphids involves disrupting their reproduction using integrated pest management methods. These will incorporate biological control, together with cultural practices, to break their rapid cloning. I have maintained aphid-free gardens for years using these techniques, without the need for chemicals. Success comes from understanding one's life habits.
Biological Warfare
- Release lady beetles consuming 50-60 aphids daily
- Introduce braconid wasps that parasitize hundreds weekly
- Apply Beauveria bassiana fungus during morning humidity
Habitat Disruption
- Prune overwintering sites on woody host plants
- Remove ant colonies farming aphids for honeydew
- Destroy alternate host plants near gardens
Cultural Controls
- Install reflective mulches to deter winged invaders
- Use drip irrigation to avoid washing off predators
- Rotate susceptible crops annually
Microbial insecticides, such as Beauveria bassiana, provide targeted control. Application of 1 to 2 billion spores per gallon should be made when the humidity exceeds 60 percent. The fungus penetrates the aphids' cuticles, causing a lethal infection. Use in conjunction with reflecting mulches, which confuse winged colonists. This two-fold treatment breaks the life cycle of infestation.
The first technique to avoid recurrence is to eliminate any overwintering sites. Prune buckthorn and the other primary hosts before winter. Apply sticky barriers to the trunks of trees, which will break serin ant access. Healthy plants resist infiltration more readily and should be fertilized properly, while also being kept from water stress. Weekly observations should be made during peak seasons.
The timing of interventions is paramount. Prevent exponential growth by implementing controls before it begins. Release predators immediately upon seeing the first colonies. Apply the microbials during the nymph stages. I schedule treatments utilizing degree-day models to track aphid development. A consistent strategy should yield permanent control, not single applications.
Read the full article: Aphid Life Cycle: Stages and Secrets
