Moles and voles go wherever they want to go, and eat whatever they want to eat. They are interested in eating the roots of your plants and some insect larvae which live among the roots. They love freshly dug soil and newly planted plants. When you plant out a bed of transplants they think you’ve prepared them a luscious buffet. They seem to be worse after a good rain when the ground is soft. As with squirrels, as many voles as you trap or kill, there seems to be a constant supply of new ones ready to take over the yard, especially if your neighbors let them run wild.
We’ve noticed that vole activity seems to be worse in shaded areas than sunny, and that these critters go crazy under any area mulched with bark or leaves. We’ve had whole areas dug up in a single night, and have even found them tunneling under some lawn during the day. These guys will just destroy new plants and tear up the ground if left unchecked. Worse, in my yard, I’ve found snakes also use the vole holes and tunnels for their own purposes.
Some people will bait the tunnels with poison, but I choose not to use poisons, especially since we have neighboring outside cats. Some people leave traps and catch moles and voles, but then you have to do something with the creatures once trapped. Eliminating all moles and voles isn’t going to happen in a forested neighborhood, but, there are some things you can do to slow them down.
First, we destroy the tunnels and holes whenever and where ever we find them. We stomp the tunnels flat, and fill the entrance holes with pea gravel. If you find one hole, there will probably be another nearby. Before I started filling the holes with pea gravel, we put rocks, bottle caps, moth balls, and other treasures into the tunnels before stomping them flat. Moth balls are especially effective at chasing these critters out of a particular tunnel.
A product called “Milky Spore” which is a bacterium, is sprinkled on lawns, and serves to kill the larvae of the Japanese beetle which may be living in your soil. These larvae are a major food source for moles, and friends have told me that using milky spore reduced the tunneling in their lawn. Milky spore is not poisonous, won’t harm pets or other wildlife, lasts in the soil for years, and is widely available in hardware stores and garden centers. As a bonus, it will reduce any problems with Japanese beetles.
When planting anything new, I mix pea gravel into the “back-fill” under and around the plant. The rocks will slow them down. I also mulch around newly planted beds with pea gravel to slow down the squirrels and the voles.
If you’re really serious, put a Camphor bean seed into the tunnel before you stomp it. They are so poisonous, one will kill a horse. After the first year, I realized the Camphor bean plants are beautiful, and that they look great growing anywhere there is some sun. They are tall, and so do best behind shorter plants. Now, I soak and plant the Camphor seeds in early spring, and then plant out the seedling plants after frost. This approach allows the roots to spread out more quickly in the area where voles are present. Be sure to wear gloves whenever working with Camphor seeds or plants, as all parts of the plant are poisonous. Even handling the seeds or the seedlings can cause a problem in sensitive people.
Other beautiful, but poisonous, plants to set out in areas you wish to protect are Daffodils and Hellebores. Their roots will grow out to protect the plants growing around them. Consider mulching with ragged Hellebores leaves you’ve trimmed back to give areas further protection. As the leaves decay, they protect the soil.
The best plan is to grow in raised beds, however. When you build the bed, put a layer of chicken wire or landscaping fabric on the ground; follow with a shallow layer of gravel, then newspaper, cardboard, or brown paper shopping bags. This suppresses the grown of any grass or weeds up into your new bed. It will break down quickly, and help retain moisture under the roots as it enriches the soil. Next, fill the bed with bagged topsoil and compost.
This type of bed will keep the voles out, though not the squirrels. Its is better for the plants, too, especially if your soil is depleted or compacted. It is very easy to plant into the fresh soil, and the plants get off to a good start. This is also an easy bed to maintain, and will never need tilling. Simply add a few inches of compost each spring, and move plants in and out as the season dictates.
Plants grown in raised beds and containers grow much better than plants put directly into the soil around our home. We get larger, lusher plants, with more flowers and fruits. The soil varies quite a bit yard to yard and from one area of a yard to another, partly because our neighborhood is situated on hills and ravines. The steep grade of our yard makes traditional double digging or tilling not only impractical, but dangerous. Building up above the present soil makes more sense, gives a better result, and allows us to put down layers of material to stop the moles and voles from digging up to get the roots of our plants.