In such cases the weeps consist of small-diameter plastic, clay or metal pipes extending through the wall to a layer of porous backfill. Typically, weeps are arranged to direct water which may have entered an assembly from outside back to the outside.
A few of several safe household chemicals to use are vinegar, dishwashing soap and rubbing alcohol, according to an Oregon State University Extension Service publication called Using Home Remedies to Control Garden Pests, (EC 1586). The publication, complete with photos, is available free of charge online.
Bonide Eight Insect Control Garden Dust. Use Bonide's Eight Garden Dust in you home gardens to control insect pests that are troublesome and hard to control. Eight Insect Garden Dust controls a variety of insects on roses and flowers as well as in vegetable gardens. The active ingredient, Permethrin 0.125% kills and continues to repel insects for up to a month. Bonide's Eight Insect Garden Dust is conveniently tinted a green color in order to blend nicely.