Groundhogs are excellent at digging, which could mean a plethora of pest holes and tunnels in your garden and yard. Their massive tunneling systems can even damage foundations supporting houses and other structures, so keeping these creatures far, far away is better than waiting until they wreak havoc around your home.
Groundhogs are fond of fruits and veggies, so orchards, fruit trees and gardens naturally attract these hungry 'hogs. Pick up any fallen fruits such as peaches, pears or apples as soon as you notice them to help keep groundhogs away. Harvest produce from your garden as soon as possible as well. If you've noticed groundhogs in the area, avoid putting produce scraps into an open compost pile until you've dealt with the issue. Otherwise, switch to a closed composting method, such as a compost barrel, which keeps foraging creatures out. Eliminating or protecting such food sources helps prevent groundhog problems.
Hot and Spicy Repellents
Groundhogs aren't fond of hot, pungent or spicy scents and tastes. Keep groundhogs away from areas such as specific garden plants or old groundhog holes by sprinkling crushed fresh garlic, hot pepper sauce or hot pepper flakes around the perimeter. Purchase hot pepper sauces or flakes in bulk to get the best price, then apply when dry weather is forecast. Apply the pepper sauce/flakes or garlic again after it rains or several days after initial application when the scent is no longer noticeable.
Cayenne pepper can also be used directly on garden plants that the groundhogs may otherwise find tasty. Mix 2 teaspoons of hot pepper sauce per quart of water, then spray on plant foliage you wish to protect. Apply again after several days or after rain, whichever comes first.
Used kitty litter comes in handy for keeping groundhogs away, too. Cats are predators of groundhogs, so the scent of cat scat can make a groundhog think cats are nearby. Sprinkle the soiled kitty litter around groundhog burrows to encourage the creatures to live elsewhere.
Castor Oil Option
Pour castor oil in and around the burrow holes when the groundhogs aren't underground. They don't care for the smell of this natural oil and will avoid it. For the garden, mix 1 part castor oil with 4 parts water in a spray bottle, shake well and apply it to leafy areas of plants you wish to protect from groundhogs.
Fence Them Out
A fence can also help keep groundhogs away from your prized plants. Build a fence at least 3 feet high around the garden, ensuring that another foot or so of fencing extends underground to prevent burrowing under the fence. Bend the fence outwards at the top, leaving the top 6 to 12 inches detached from the posts holding up the entire fence. Any climbing creature will have a difficult time getting into the garden, as the floppy fence will bend out farther as they near the top.
Water as Repellent
A motion-activated sprinkler is a great way to help keep groundhogs away from a garden bed or out of certain areas of a yard. Any time a groundhog comes within range of the sprinkler, it's treated with a spurt of water. After getting sprayed several times, the animal will likely not visit that area again. You may need to use several sprinklers to cover a large area.