In some cases in Yardener’s Helper we offer as an option to control certain pest insects the use of commercially available live beneficial insects. These techniques are viable commercial options, but for the home consumer, they are marginal as options in our view though some folks feel real strongly about the issue. So we offer beneficial insects as an option in some cases. Homeowners with greenhouses or sunspaces may find releasing beneficial insects very valuable in protecting those plants from problems. Outside in the garden however, we feel that in most cases, a good set of plant care practices will encourage the natural beneficial insect population sufficient to do the job.
In our opinion, when you use 3 to 4 inches of organic mulch on your gardens and you do not use broad spectrum insecticides in your yard, the beneficial insects will naturally congregate in your ecological niche.