Horticultural oils and soaps also work well to knockdown most insect and arachnid pests.
Oils can clog stomata so I alternate and the soap spray cleans them up.
Oils should never be used in conjunction with Sulfur as the combination is phytotoxic.
These agents are contact killers, so total coverage is required for knockdown. Small plants can be dunked, but be careful, as the dilution should be much higher than spray ratios.
After dunking, it is important to dry plants relatively quickly, a dry climate, and air movement are your friends.