A single application in the Spring protects sprouting plants and new growth for the entire growing season. Repellent does not come in contact with leaves or fruit. Proven Effective in Years of Field Studies 100% dried blood is recognized as the leading deer repellent in university studies and field trials by the U.S. Department of Agriculture. Triggers the flight response in deer. Safe to use around children and pets. The repellent is continuously released from repellent station, triggering a deer s instinct to avoid predator activity.