Asparagus aphid
1 host plant
Last updated
Asparagus aphids cause distinctive blue-green, bushy growth distortion on asparagus ferns, making the feathery foliage appear stunted and witch-broom-like. You will find small, gray-green aphids clustered on new fern growth starting in late spring. Heavy infestations weaken the crown for the following season by reducing the plant's ability to photosynthesize and store energy through summer.
Cut and remove infested ferns in fall to eliminate overwintering eggs. Lady beetles and parasitic wasps provide biological control during the growing season. A strong water spray knocks aphids off ferns without chemical intervention. If populations threaten crown vigor, insecticidal soap applied directly to colonies offers targeted control.
Quick Reference
Cultural Controls
- biological control Many parasites and predators attack aphid.
- Monitor the proportion of aphid mummies to unparasitized adults and the number of predators such as lady beetles.
- If the biocontrol agents appear to be gaining control, avoid sprays which would disrupt this system.
- Most products available for aphid control are highly disruptive of natural enemies.
- Management-cultural control Aphid populations tend to be higher in plants that are fertilized liberally with nitrogen.
- Prune out suckers...