Get rid of fruit flies with the best products and proper steps in our Fruit Fly Control Guide. The ultraviolet light bulbs in fly light traps need to be replaced on scheduled dates, usually every 4-6 months. These bulbs should be changed even if they have not burned out.Aug 29, 2007 · Thoroughly wash the pot (leaving the plant submerged as much as possible) making sure you get rid of all dirt and stains. Dry the pot. Or buy a new pot (same size as existing) and toss the old one in the garbage. Give the plant another dunk in clean water and put both the plant, pot and new soil in a separate room from the others.