Groundhogs are easily frightened so making frequent visits to your garden may be enough to deter them. Constructing a scarecrow that makes noise and moves when the wind blows can also be suitable to scare away groundhogs. However, if the groundhog is more persistent there are a number of solutions. The most permanent way to keep groundhogs out of your garden is to exclude them with a fence. The fence only needs to be about three feet high. To stop groundhogs from burrowing underneath, the fence should be buried about one foot beneath the ground, with a section of the fence facing outwards in a backwards ’L’ shape. If fencing is not an option, you can cover the plants with milk jugs with the bottom cut out, or covers can be purchased from garden supply stores.
Repellents may also be used to deter groundhogs from your garden. There are also many homemade remedies you can try. A diluted solution of hot sauce (one tablespoon of hot sauce mixed in one gallon of water) sprayed directly on the veggies or around the perimeter of the garden may deter groundhogs. Remember to wash vegetables and fruit thoroughly before consuming them yourself.
Other easy deterrents to try are scare devices. Motion-sensitive lights, alarms, or sprinklers can be used to scare groundhogs away. You can also build your own scare device. Insert a pole into the ground near the garden and hang a metal garbage lid or pie plates on the post. When the wind blows this will create motion and noise to scare the groundhogs. You can also use scare tape which can be purchased at hardware or garden supply stores.
As burrowers, groundhogs can also be disturbed through the introduction of vibrations in the ground they inhabit. Spinning pinwheels can be installed at the entry. When the wind blows, the pinwheel spins and creates vibrations that groundhogs can feel and will dislike in their underground home. Another option is letting vegetation grow around the entry/exit hole. Restricted visibility at the entry/exit point of the burrow will make the groundhog feel insecure and may help encourage relocation.
To flush out the hole place take a glass container, add about quarter cup of water. Add about 2 table spoons of detergent (or soap) to the water and stir. Take two cups of regular Ammonia available in pharmacies etc., and add this to the solution of detergent/soap. This is now a very very close substitute for Sudsy Ammonia. Pour the mixture in the hole/burrow where the animal lives. Make sure you pour it so that much of it can flow deep into the hole. Leave the area alone. Sometimes the animals will start leaving very shortly. If there are young ones present, then the process takes longer as the animal will first find a new home and then take the young ones along. Repeat if necessary.