How to Spray Concord Grapes for Bugs

Protecting your grapevines from pests is easy.

For organic gardeners, growing concord grapes can be difficult. A plethora of annoying, plant-destroying insects, like whiteflies and mealybugs, can often ruin a crop of concord grapes if they haven't been sprayed properly. The use of insecticides can seem dangerous, especially on foods. However, a type of insecticide known as pyrethrum has been proven safe for food products. Pyrethrum is composed of an all-natural product that comes from ground chrysanthemum heads. Pyrethrum kills insects on contact, and can be used up to one day before harvesting.

Things You'll Need

• Protective eye wear
• Chemical-resistant gloves
• Face mask
• Liquid pyrethrum or rotenone/pyrethrum (non-organic)
• Gallon bucket
• Empty spray bottle
• Funnel

Instructions

1. Put on the protective eye wear, gloves and face mask to protect your skin and lungs from the insecticide. Fill the bucket with one gallon of regular tap water.

2. Mix about two teaspoons of liquid pyrethrum or a rotenone/pyrethrum mixture in with the full one-gallon bucket of water. For areas up to an acre, mix one quart of pyrethrum with 100 gallons of water. A two-gallon hand-held garden sprayer can also be used instead of a spray bottle. For this, mix in four teaspoons of insecticide with two gallons of water.

3. Funnel the pyrethrum and water mixture into the empty spray bottle. Make sure the spray bottle is new; never use bottles that once held cleaning fluid. Screw the nozzle onto the spray bottle.

4. Spray the concord grapes and the surrounding area during early morning or afternoon, making sure the fruit and leaves are completely saturated. Avoid spraying when pollinators such as bees and butterflies are in the vicinity; pyrethrum is hazardous to these useful bugs as well.

5. Repeat the process in 7 to 10 days or more often if bugs reappear quickly. Pyrethrum affects the bugs on contact, causing nervous system malfunction and death. Natural pyrethrum loses its effectiveness after about 12 hours.

Tips & Warnings

• Pyrethrum can also be used to treat animals with fleas, ticks or lice.

• Pyrethrum can cause dermatitis and irritation in people with allergies. Wear long sleeves, long pants and rubber footwear when using pyrethrum. Rotenone/pyrethrum mixtures are not certified for organic farmers, and can cause possible nerve damage in vertebrates. Keep rotenone products away from ponds, rivers and streams, as it can kill fish and other aquatic creatures.

References

• Cornell Gardening Resources
• BioControl Network
• Hortiscope: Questions on Grapevines

Resources

• Rotenone Hazards
• Pyrethrum Insecticide MSDS