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.
Step 3. Place 8 oz. of Tempo insecticide in a garden sprayer if you have a small infestation. If you have a large infestation, it is okay to use 16 oz. of the Tempo concentrate. Step 4. Add 1 gallon of water to the garden sprayer, and mix the two ingredients together.