One of the unwanted visitors to the spring garden arrives just about now. That mass of tiny pests that cloak the new growth on your roses, elderberries, viburnums, or peach trees are at best an unsightly nuisance and at worst, creatures that can damage tender new growth on plants and spread disease. They’re aphids!
- Over 200 species; almost every plant has one or more aphid species that occasionally feeds on it.
- Plants in the rose, aster, and conifer families support the greatest numbers of aphid species.
- In spring, eggs hatch into females and during the warm growing season, each female can produce as many as 12 offspring a day.
- An aphid can go from a newborn to a reproducing adult in about a week.
What they look like:
- Small, pear-shaped, soft-bodied insects that are often green, with others that are white, yellow, pink, brown, black, or mottled.
- Some even look waxy or woolly.
- They have “exhaust pipe” projections at the rear of the abdomen that are their trademark.
What they do:
- They’re often seen in masses, covering succulent new growth on plants.
- They suck up plant liquids that can weaken plant growth, cause leaves to yellow, curl, or drop early.
- Some species can distort plant stems or fruit or cause galls on stems, leaves, or roots.
- As they feed, they produce honeydew that attract ants.
- Ants will protect aphids from predators.
- Any honeydew the ants don’t consume can end up supporting the growth of black sooty mold.
How to manage them:
- Avoid using high nitrogen fertilizer – the succulent plant growth attracts aphids.
- Monitor for their presence, including ants and honeydew to take early action.
- Knock them to the ground with a strong stream of water.
- Encourage natural enemies including lady beetles, soldier beetles, lacewings and syrphid fly larvae – and watch them go!
Learn more about aphids here, and how to attract and keep natural enemies in your garden.