When I was building and preparing my garden beds about eight years ago, little did I know that I would encounter one of the smallest, and yet, most threatening, creatures to a garden--the vole. Since my house was part of new construction, it would be a few years before the voles moved back in after their exit from the disruption of the building process. It was not long before they began by burrowing small holes here and there. Then, I noticed leaning plants with root damage. Spring tulips were devoured. The roots of shrubs, small trees, and perennials were nibbled until there was no hope for the survival of these plants.
For a couple of years, they feasted on my garden as if I had offered it to them as a gift. It was a very difficult time as I lost plant after plant, shrub after shrub, small tree after small tree. In one winter, they ate over 300 tulip bulbs I planted around the garden beds. Many times as I thought I had found the last dying plant with roots nibbled to the stem, I would find another and another and another. My carefully planted garden was disappearing almost as fast as I had created it. There was a time I felt so exhausted, I thought it would be best to return all my garden beds to lawn and give up.
Before I gave up, I decided to find out as much as I could about their behavior and deterrents to try to control them. I spent a lot of time researching their behavior and methods of controlling them. For the last few years, I have been able to keep them at bay. I still may find a nibbled hosta or some vole holes, but, for the most part, I feel I have them under control...cross my fingers in hope. Although I have some experience deterring these persistent creatures, I would not say I am an expert. I am still learning and experimenting and would love to hear about any other methods gardeners have tried with success.
I do not have any photographs of the damage voles caused in my garden, but Clare at Curbstone Valley Farm has some very good photographs of the damage they have caused in her garden. Her photographs illustrate the exact kind of damage I experience in my garden as well.
About the Vole
The vole is a small rodent that resembles a mouse. It is sometimes referred to as a field mouse or meadow mouse.
Young voles reach maturity at one month of age and can have up to 10 litters a year with five to 10 in each litter. They can multiply very quickly if they find an area that can provide enough food.
To avoid predators, voles limit their time above ground by burrowing near the base of a plant and feasting on the roots until there is nothing left. Voles can live from two to 16 months.
Pine voles or woodland voles nest underground and meadow voles nest above ground.
Although voles can be pests, they do have a role in nature. Their habits and behaviors ensure that nutrients are spread and integrated into the upper layers of soil. Mycorrhizal fungi, a soil nutrient, is dispersed by the vole.
Voles are a food source for many predatory birds, snakes, foxes, and cats.
Habits and Behaviors
Voles eat grasses, seeds, roots, leaves, bark, bulbs, tubers, nuts, berries, and fungi. They dig runways near the surface of the ground, and create deep underground burrows. They sometimes use the existing runways created by moles. These runways and burrows protect them from predators.
Vole predators include: hawks, owls, kestrels, cats, bobcats, foxes, coyotes, snakes, badgers, weasels, skunks, minks, and humans.
Voles are primarily nocturnal, but they do sometimes come out during the day.
Vole Deterrents and Controls
Narcissi (daffodils) are poisonous to voles, and they will not eat them. By planting them throughout the planting beds, the garden becomes less attractive to voles.
Sharp Gravel or Stone
Use sharp gravel around plants and bulbs because voles do not like digging around sharp edges. Sharp granite chips (chicken grit), crushed oyster shells, and VoleBloc from Permatill work to deter voles indefinitely when placed around the base and roots of plants.
For existing plants, dig the sharp gravel product down to a depth of 10 to 12 inches and about 3 inches wide around the plant.
For new plants, pour two inches of the sharp gravel product on the bottom of the planting hole, and surround the plant root with a 3 to 4 inch wide channel of the sharp gravel to the top of the soil surface. Backfill with soil.
Plant bulbs surrounded by sharp gravel, and then backfill with soil.
When planting bulbs, encase them in a wire mesh cage. Make sure the holes of the wire mesh are small enough to prevent voles from fitting through to the bulbs. This method is the only way I can grow tulips in my garden without the voles eating them all. I created a raised bed encased in wire mesh on the bottom and sides where I plant the tulips every year.
When planting new plants, encase the root ball in wire mesh before planting. Make sure that the holes of the wire mesh are small enough to prevent voles from fitting through but are large enough to allow roots to spread out of the mesh. This is not recommended for trees.
Castor Oil Pellets, Granules, or Spray
The castor bean plant is poisonous to animals and humans and is avoided by voles. The pellets or granules smell, taste, and feel bad to the voles. Most castor oil granules last up to three months, and then must be reapplied. Spread around areas where vole activity has been seen. Pour some in vole holes. Sprinkle around the base of plants and work in the soil around plants to protect them from vole damage.
I have used several of these products by various manufacturers. They all perform similarly.
Some of the castor oil products come in a convenient spray bottle that can be sprayed over a wide area. This works very well when sprayed in the vole holes and tunnels and over the affected area.
Capsaicin is the main ingredient in chili peppers that causes irritation. Hot chili powder or cayenne pepper powder can be used to deter voles because it is unpleasant to them. On a calm day, spread around areas where vole activity has been seen. Pour some in vole holes and tunnels, and work in the soil around plants to protect them. This must be reapplied frequently and after rain.
Many products mimic the odor of predator urine to deter voles. Voles will flee an area that smells of predator urine. I tried one of these products, and it worked very well. However, these products can be very expensive. Therefore, I tried using a homemade version. This does have a gross factor, so it is not for everyone but the desperate. I use natural clumping cat litter made from corn, wheat, or walnut shells. From time to time, I use these urine clumps as vole deterrents by placing them in vole holes. My cats are not on any medications and eat an all natural diet, so these clumps simply decompose over time. I would not recommend using the homemade version around your vegetable or herb garden or any edible plants.
Vitamin D3 (cholecalciferol) Rodenticides
Vitamin D3 rodenticides are mostly safe and will control voles without harming their predators or the environment. Follow the dosage instructions on the package. Place the rodenticide in the vole hole. Sometimes it is helpful to mix the pellets with apple juice and peanut butter to make them more attractive to the voles.
Try to only use rodenticides in desperate cases because voles are a beneficial component to the environment, spreading nutrients throughout the soil and feeding many predators. Rodenticides with cholecalciferol usually have small enough doses as to not injure cats, dogs, or other animals. However, there have been cases of cholecalciferol poisoning in cats and small dogs, so be very mindful of this as you use these products.
When using these rodenticides, be sure to follow the instructions carefully.
There are many traps on the market for trapping voles. The key thing to remember is to place the traps near or inside the vole hole and cover the trap with a clay or heavy planter or some other type of covering. The vole needs to feel it is not exposed to predators as it enters the trap.
Clean and Clear Plant Debris From Garden Beds in the Fall
I used to do my garden cleaning in the spring, leaving the fall leaves and plant debris to act as a mulch to shelter garden plants through the winter. This is exactly the type of shelter voles prefer as they tunnel through the leaves and debris to the base of plants and plant roots. I have seen less vole activity since I have begun my garden cleaning in the fall.
Attract Birds of Prey
|Cooper's Hawk - National Digital Library|
If you do not have many trees in your yard for birds of prey to use as perches, erect perching poles about 10 to 15 feet high near the areas where you have vole activity. Add nest boxes for owls and hawks to attract them to your garden.
Domestic cats are very helpful in hunting and catching voles. My cats have found a few over the years throughout the yard and garden.
Jack Russell Terrier Dogs
These are excellent vole hunters. They are known as 'ratting' dogs and will keep the vole population in check. Be mindful that although these are excellent vole catchers, they can wreak havoc in the garden with their digging behavior.
Many large snakes prey on voles and, if left alone, can be very efficient in ridding your garden of voles. Black rat snakes, prairie kingsnakes, large garter snakes, and bull snakes are just a few of the snakes that prey on voles. These snakes are not poisonous and will usually dash away if disturbed.
Walk Around the Garden Once a Month
I have noticed if I walk around the garden at least once a month looking for vole holes and damage, I can usually curtail any serious damage before it becomes a real problem. Voles use snow as a shelter to tunnel through to plants. Check the garden after snow melts to see if there is any vole damage.
Some things I have learned:
- Rosemary deters voles. I once planted a few tulip bulbs around a rosemary plant. The voles ate all the bulbs in the garden bed except the ones near the rosemary plant.
- Each year is different. Some years the vole populations are larger and cause more damage than other years.
- In my experience, hostas and tulip bulbs are vole favorites. I must take measures to protect all of these in my garden.
- I have a lot of large perennial beds, and these are favored by voles because so many plants are in close proximity and the mulch and soil is usually softer and easier for tunneling than the hard clay soil of the lawn. If I had known that voles would be a problem when I planned my garden beds, I would have created smaller beds with lawn in between.
- Avoid placing bird feeders over mulched areas or near stepping stones and walls
Bird feeder waste attracts voles. If the bird feeder is over mulch, the voles will tunnel under the mulch to get to the bird seed. They will also nibble on nearby plants and bulbs. They will also tunnel under stepping stones or next to walls perhaps even creating burrows.
I had a bird feeder in a mulched area and lost several plants over a season because the voles created some burrows near the bird feeder area and chewed the roots from these plants. I stopped feeding the birds for several years until I began again this year. I am experimenting with placing the bird feeder in a tree over a grassy area. I have had some vole activity, but I think I was able to deter them before there was any damage. I filled the holes with the sharp gravel and castor oil granules. I also spread some cayenne pepper powder around the area.
- Voles like to burrow next to houses or walls or under porches because of the refuge from predators these areas provide. Dig down a few inches all around these areas and fill with the sharp gravel to prevent them from using these areas for burrowing.
Voles were burrowing under my porch and sidewalk and were, therefore, closer to many of my plants in the adjacent planting beds. It was a lot of work, but my husband and I dug around all these areas and filled them with sharp gravel. We have not seen any vole activity in these areas since we added the sharp gravel.
What methods do you use to control voles in your garden?
I am joining Beth at Plant Postings for Lessons Learned. Beth hosts this meme on the first of the month prior to the seasonal solstice or equinox. Garden bloggers share lessons learned in the garden.
© copyright 2012 Michelle A. Potter