Otherwise, insecticidal soap and summer horticultural oil are pesticides that control aphids. Read and follow label directions. Repeat treatment as needed. There is another pest called a leaf roller. It is a caterpillar that spins sticky webbing and uses it to seal a rolled-up leaf to conceal itself while it feeds.
Some leaf rollers feed on new growth and are especially harmful to plants.
Look for silken threads and tightly rolled leaves containing small caterpillars about an inch long. To control leaf rollers, pick off and dispose of rolled leaves. Spray or dust the foliage with Dipel, Thuricide or other pesticide containing Bacillus thuringiensis as its active ingredient. Follow label directions. I have been trying to control them for two years, but no matter what I do they still damage my grass.