how can i kill or get rid of the white aphids on my shrubs and plants outside?
New Castle County Delaware
Aphids and white flies are fairly easy to control. Aphids are a favorite food for several of our natural predator insects, so if you have aphids, usually ladybird beetles and lacewings will show up. On the other hand, in order to avoid killing the predator insects, you could spray the aphids or white flies with insecticidal soap or horticultural oil, but be very careful not to spray those products on hot, sunny, humid days (over 85deg.). In doing so, you could 'French fry' the plants.
On hot days, you could simply spray the plants with a forceful water spray. That will knock the insects off the plants, at least temporarily.