All natural deer repellent lasts up to 3-4 months during growing season, up to 6 months over winter. Repels by scent for best results. Non-offensive odor to people. Active ingredient is dried blood meal, recognized by the EPA as environmentally safe. OMRI listed Developed for commercial forest planting in Sweden, now produced in the USA. Rainfast in 24 hours. Repels deer, rabbit and elk. Acts as a foliar feed fertilizer on many plants.