there is a completely organic product called serenade. you can spray up till harvest. i too hate spraying my buds, but anything is better than mold. if you have 3 weeks left, i would burn the sulfur. i usually quit using it the last 3 weeks, but if i saw it at 20 days, i would def. burn the sulfur. its only gettin worse if left untreated. burning the sulfur should give you a 2-3 week window to let you finish your girls out-w/ NO MOLD!!!!!