How to Protect Flower Bulbs from Voles
Voles are cute little mouse-like rodents with long tails and big appetites. Unlike moles, which are carnivores, voles are strictly herbivores. They eat plant roots and tubers, mushrooms, berries, seeds and nuts, and the bark of shrubs and small trees. And, unfortunately, they have a special fondness for flower bulbs.
If you have voles in your yard, you may occasionally see them out of the corner of your eye as they zip from one hiding place to another. Or, you may notice their compacted “travel runways” where they move across the soil or lawn. Voles also dig shallow tunnels that leave the soil underfoot feeling spongy. Quarter-size holes on the soil surface may indicate an entrance to one of their tunnels or burrows.
Having a couple voles around isn’t worth worrying about. But things can quickly get out of hand. During a female vole’s 12-month lifespan, she can produce 50-80 offspring. And, since these busy little rodents don’t hibernate during in the winter months, they are always looking for their next meal.
7 Ways to Minimize Vole Damage
Tidy Up. Voles love messy areas with long grass, dead leaves, plant debris and mulch. If you have a garden, you probably can’t eliminate all of these vole-friendly places, but if you can minimize them, you will make the area less appealing.
Natural Barriers. Planting bulbs beside a walkway, against the house, between the sidewalk and road, or inside a planter makes them less accessible to burrowing voles. Small garden beds, surrounded by lawn or backed up to a structure, are somewhat less appealing than large beds with soft, welcoming soil.
Fencing. To create a vole-proof barrier, use steel mesh with openings that are no more than 1/4″ square. Surround the garden or planting area with the mesh, making sure it extends 12” below ground and at least 12” above ground. Ideally, the bottom of the bed should be protected as well.
Another option is to fashion open-top, bulb cages from the same type of steel mesh. Bury the cages and plant the bulbs inside. Cover the soil surface with a 1″ layer of gravel to discourage digging from the top down. You can also cut out the bottom of a nursery pot, sink the pot into the ground and plant the bulbs inside.
Deterrents. To make tunneling more difficult, surround the planting areas with a band of crushed gravel. When planting your bulbs, add granite chips or crushed oyster shells to the planting hole to deter chewing. For added protection, mix in red pepper flakes and powdered garlic.
Traps. Snap traps can be placed in vole runways or near their entry holes. Use peanut butter for bait and check them frequently. To reduce the risk to pets, and other wildlife, cover the traps with a box that has small entrance and exit holes.
Repellents. Castor oil granules and liquid sprays can be used to repel voles. Fox and coyote urine (available commercially) are also reputed to be effective. Remember that scent repellents need to be reapplied as directed and may not be effective in the soil.
Here are a few other tips for controlling voles.
Think about where you place your bird feeders. Dropped seeds and shells attract voles, so try to locate feeders away from flower beds, especially beds that may contain flower bulbs.
Domestic cats are great at catching voles. Voles are also eaten by owls, hawks, foxes, bobcats, coyotes and some kinds of snakes.
It’s good to know that vole problems usually come and go with the peaks and valleys of their population cycles. If you give some of these strategies a try, please share the results — other suggestions welcome!