Our groundhog cases nearly always start the same way: damage done in broad daylight, out in the open, which alone separates it from nearly every other digger on this list — most animals that raid a garden do it under cover of dark. The burrow entrance is the other tell: eight inches wide or more, with a substantial mound of excavated dirt beside it, usually somewhere along a fence line or under a shed. A groundhog can level an entire row of leafy greens in a single sitting, feeding calmly at midday like it belongs there. The fence that actually stops one needs two features most gardeners skip: the top foot left unattached so it flops outward under a climbing weight, and the bottom bent ninety degrees and buried a foot deep so digging under fails too. Predator-scent granules around the burrow fade within about ten days once nothing predatory ever follows the smell. A motion-triggered sprinkler works at first, but a groundhog defending a den close to the garden will eventually push straight through the spray to get back to its favorite bed.
Signs it's them
- Soil disturbance: Mounds + tunnels.
- What gets hit: Leaves + stems.
The distinguishing check: Look for a large burrow entrance (8+ in wide) with a substantial dirt mound, active during full daylight — unlike most garden diggers, groundhogs feed openly at midday and can level a whole row of leafy greens in one sitting.
What actually works
Exclusion beats deterrence — every time, for every culprit on this list. Start here:
Fence below and above ground
3-ft welded wire fence with the top 12 in left unattached to flop outward (stops climbing) and the bottom bent 90° outward and buried 12 in (stops digging under)
Deterrents — honest expectations
Deterrents are a bridge while exclusion goes in, not a fix. Every one of them fades as the animal learns nothing bad actually happens.
Predator urine granules (coyote/fox)
Apply around the burrow entrance and garden perimeter.
Habituates within about ten days once no predator ever shows up.
Expect about 10 days before they adjust.
Motion-activated sprinkler
Cover the main approach route from the burrow.
Effective at first, but a determined groundhog defending a nearby den will push through it.
Expect about 21 days before they adjust.
Never do this
- Flooding or gassing burrows — rarely permanent and can affect neighboring dens
- Ultrasonic repellers — no reliable evidence against groundhogs
- Relocating a live-trapped groundhog yourself — often restricted without a permit and usually fatal to the animal in unfamiliar territory
A groundhog denned well away from the garden, browsing clover in the yard, is easy to live with — full exclusion is for the beds it’s already found.
Region note: Groundhog (woodchuck) trouble is concentrated in the East & Midwest. If you garden elsewhere, the same damage most likely has a different author — the related guides below cover the usual suspects.