Garlic Spray for Fruit Trees

Garlic spray can be an effective insect repellant.

When fruit trees are attacked by pests, including birds, rodents, insects and deer, or by fungus and molds, garlic spray can be an effective way to deter the pests. Garlic spray remedies are a natural alternative to traditional chemically based insecticides and pesticides.

Benefits of Garlic

According to the University of Maryland Medical Center, garlic has been used as a food and medicine dating back to approximately 3000 to 2500 BC. Garlic contains antioxidants that help support the immune system. In addition, garlic may have antiviral, antibacterial, anti-parasitic and anti-fungal properties due in part to the presence of alliin, an odorless sulfur-containing compound. Sulfur is used in commercial preparations of fruit tree insecticides, pesticides and fungicides.

Garlic Spray Uses

Garlic spray is considered a multipurpose spray, as it treats or helps control many problematic issues for fruit trees.

According to Michigan State Horticulture Extension, common fruit tree insect pests include maggots, tarnished plant bugs, moths, leaf rollers and borers. In addition, fruit trees can be affected by the fungus diseases of scab, fruit rot, leaf spot and cedar apple rust. Wildlife such as rabbits and deer often damage fruit trees.

Garlic spray helps to deter wildlife with its scent. The anti-fungal and antiviral properties of garlic spray help control fungus, and the alliin component of garlic spray serves as an insecticide.

Garlic Spray Recipe

The following recipe for an insecticidal garlic spray from the North Dakota State University Extension Service is said to work best if directly applied to the target insects.

Finely chop about 12 garlic cloves. Soak the chopped cloves overnight in one pint of mineral oil. Strain and use the oil as a spray. It can be diluted with water and a drop or two of liquid soap can be added to make a more effective insecticide. Ivory liquid soap and Murphy's Oil soap are two recommended soaps.

Spraying Schedule

The University of Illinois says the key to an effective spraying program for fruit trees is to be consistent and persistent. Dormant oil sprays are applied during the dormant stage of the fruit tree. Thereafter, regular sprays with a multipurpose spray, such as garlic spray, begin when the green is about a half-inch out of the leaf buds, then again at the time when the fruit buds show color. This should be followed by regular spraying every 10 days. Stop spraying about two weeks before harvest.

Garlic and Beneficial Insects

There are concerns about garlic spray's effects on beneficial insects. In a preliminary study by the Texas Agriculture Extension Service, garlic sprays did not appear to deter or hurt beneficial insects, such as ladybugs and bees. However, it did appear to help control destructive stink bugs, greenbugs and nematodes.

References

• University of Maryland Medical Center: Garlic
• Michigan State Horticulture Extension: Common Tree Fruit Insects
• Texas Agricultural Extension Service: Garlic Spray May Keep Pests Away
• NDSU Extension Service: Questions on Insecticides
• University of Illinois Extension: Fruit Tree Spray Schedule

Resources

• Cornell University's Extension Toxicology Network: Sulfur
• University of Kentucky Agriculture: Midwest Tree Fruit Pest Management Handbook