Home remedies sometimes work with these insect-eating mammals. They tunnel to find earthworms, grub worms and insect larvae to eat. Moles can be controlled to some degree with hot-pepper and castor-oil products or mixtures of these ingredients. Injecting the materials into the ground in the problem areas is more effective than spraying the surface. Planting castor beans around the perimeter of the yard or garden can help, too.
FORMULA
The formula for the castor-oil repellent can be made by using a blender to combine 1/4 cup of unrefined castor oil (can be purchased at most pharmacies) and 2 tablespoons of a dishwashing liquid. Blend the two together, add 6 tablespoons water, and blend again. Combine the concentrated mixture with water at a rate of 2 tablespoons of solution to 1 gallon of water. Use a watering can or sprayer to liberally apply the solution to areas where moles are active. The above mixture will cover approximately 300 square feet.
The repellent will be most effective where it can be watered into the moist soil surrounding surface tunnels made by moles. Areas that receive extensive irrigation will quickly loose the repellent to leaching. For best results, spray the entire area needing protection; moles will burrow under a perimeter treatment.
The repellent may need to be reapplied before moles depart. Once moles move elsewhere, the solution usually remains effective for 30 to 60 days
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