THE GROW SHOP PRODUCT TIP: PYRETHRUM KILLS INSECTS ON CONTACT. WE SUGGEST MOVING PLANTS AWAY FROM HID LIGHTING WHEN USING PYRETHRUM. SPRAY TO RUN OFF BOTH SIDES OF THE LEAVES AND LET THE PRODUCT SOAK INTO THE PLANT TISSUE. ONCE DRIED SPRAY THE PLANT WITH WATER TO WASH OFF RESIDUAL PYRETHRUM THEN LET THE PLANT DRY AGAIN. YOUR PLANT HAS BEEN TREATED AND IS READY TO GO BACK UNDER HID LIGHTING. MAKE SURE YOUR PLANTS PHOTOPERIOD IS NOT INTERRUPTED WHILE UNDERTAKING THIS PROCESS.