Spidex Vital Plus contains living creatures and can be affected by any chemical pesticides used within the previous few weeks. As a general guide, refrain from using Natural Pyrethrum or SB Plant Invigorator 2 days prior to use. Other chemical insecticides can have long lasting residues that could harm the predatory mites for much longer periods. Refrain from using these products or check with Dragonfli for information on the effect of these products on the predatory mites.