It depends on the pest. I am mainly concerned with spider mites, mealy bugs and scale. For many, a solution of 1 Tablespoon / 15ml of liquid dish soap in 1 quart / liter of water works.
For spider mites it must be sprayed on all surfaces of the plant, plus the potting medium. This does not kill eggs. They have short generations, shorter with warmer weather. So repeat spraying with soap water is needed at 4-5 day intervals for 3-4 repetitions.
You need to pay attention to signs of spider mite attack, and be prepared to treat all your plants quickly when it comes back - because it will come back.
Mealy bugs or scale, and their eggs, may be killed if you submerge the entire plant in the soap solution overnight. If not, rotating applications of systemic insecticides will be needed.
I only rarely have bug issues. Spider mites during warm and dry weather are my worst arthropod pest.
|