Natural ways to keep mice at bay

It’s not only pets and domestic animals that have lived in close contact with humans since the beginning of time — mice and rats have too. But they differ from other animal species that we share space with. Although they are occasionally depicted in popular culture as cute and harmless (think Mickey Mouse, or Remy from the film Ratatouille), mice and rats trigger a deep-seated, ancient fear in us, because they are invasive, voracious and disease-carrying.

The garden can accommodate various rodent species including the house mouse (Mus domesticus), wild mouse (Apodemus sylvaticus), brown rat (Norwegian rat or, more colloquially, wharf rat), the less widespread black rat (Rattus rattus) and voles (like the Microtus savii or Microtus arvalis, known as the common vole). While rats and mice belong to the Muridae family, voles are classified in the Cricetidae family. Rats and mice are omnivores, feeding mainly on plants, as well as on insects and animal matter, including food scraps from our rubbish or compost. Today we look at how to keep mice and other rodents away from the garden and vegetable patch.

Mice and other rodents in the garden and vegetable patch: the damage

Rodents can spiral out of control because they multiply rapidly: they begin reproducing from a young age, have short gestation periods and produce large litters. Their ideal habitat is one that provides abundant food and hiding places.

The damage caused by mice and other rodents in gardens and vegetable patches can have both economic and health-related consequences. While searching for potential food sources and building their burrows, they “taste” everything they come across by gnawing it, thereby damaging any object or material. They damage plants by stripping the bark of stems and branches, and attacking roots, bulbs and leaves. They damage crops by plundering seeds and gnawing on fruits and vegetables. What’s more, they dig tunnels underground; this is particularly true for voles, but also for other rodents. Finally, they can spread diseases, either directly or through their parasites, and contaminate anything that comes into contact with their faeces, urine, etc. Feeding on various parts of plants in the garden and countryside, they cause the most damage in winter when food resources are scarce elsewhere.

You can tell if rodents are present by the traces they leave behind: dens, trails along walls or hedges, droppings, tracks and gnaw marks. Another clue is holes in the ground: don’t confuse vole activity with that of moles, as the latter are insectivorous and don’t eat vegetables, roots, bulbs or seeds. Moles' earthen mounds are typically large, rounded and arranged in a regular pattern, with the opening at the top, while vole mounds are elongated, flat and irregular, with the opening at the side. Rodents can also utilise tunnels created by other animals, such as moles: by the way, here are our tips for keeping moles away from the vegetable patch and garden.

How to keep mice and other rodents away from your garden

Eliminating mice in the garden and vegetable patch starts with prevention, in other words, making the environment inhospitable. Since rodents settle and reproduce where they can easily find food and shelter, these are precisely the factors that need to be addressed to keep them away. In the long run the most effective strategy is prevention, rather than directly targeting them with traps and specific poisons (rodenticides).

A clean garden is unappealing to rodents, so:

• Eliminate food sources: store pet and farm animal food in closed containers and out of reach; remove any leftovers from bowls and feeders; don’t leave food out for strays or wild animals. The same goes for stocks of seeds and bulbs for your garden and vegetable patch.

• Dispose of rubbish properly by placing it in the appropriate closed bins.

• Don’t throw waste animal matter (meat, fish, cheese, etc.) into the compost bin.

• Keep everywhere clean and tidy, because tall grass, wood piles and mounds of rubble or debris provide convenient hiding places. Other areas to take care of are stables, chicken coops, dog runs and other pet enclosures.

To clean grass and weeds, depending on the situation you can use a brushcutter, wheeled brushcutter or flail mower. With the right cutting attachment, a brushcutter can also be used for pruning. To thin out shrubs and hedges in order to make them less hospitable to rodents, you can also use manual tools such as loppers, or power tools such as a chainsaw. The latter is also useful for reduce the length of pruned branches so they can fit on the fireplace or be taken for disposal at the recycling centre. Whenever putting the garden in order involves transporting grass clippings, branches or other heavy and bulky materials, a transporter comes in very handy.

Another way to keep mice and other rodents away from the garden is to encourage predators, including cats, birds of prey such as owls, but also foxes and weasels. Domestic cats themselves are adept hunters of smaller rodents like mice and young rats.

To keep mice and the like away, you can purchase ultrasonic pest repellers; however, their effectiveness in deterring rodents is questionable, plus they disturb animals such as bats. Among the natural mice deterrents you can experiment with are poisonous plants such as daffodils and hyacinths, which create a “flower fence” that protects the vegetable patch, especially when used in combination with other rodent control methods. Alternatively, you can protect your vegetable patch or allotment from rodents by erecting an actual fence, one made of thick wire mesh and supported by poles, with one part buried and bent outwards at a 90-degree angle.

Direct control of mice, rats, etc. involves the use of traps and/or rodenticides. But this only temporarily addresses the symptoms rather than tackling the real causes of the problem: we talked about this in the section above on prevention. The goal should be to protect the garden and vegetable patch from the damage rodents cause, not to kill them or to cause them suffering. Furthermore, whether you are using traps or rodenticides, consider that rodents are naturally wary of new things introduced into their environment, so it will take time to get results. It is also important that traps and poisoned baits do not become a danger to other animals – including pets, farm animals and wildlife – or to people, especially children.

There are various types of traps, including live traps designed for capturing and releasing rodents at a distance, as well as snap traps. There are also a variety of rodenticides, with different active ingredients and mechanisms of action on the rodents’ body. These should be used with food baits placed in special bait boxes designed to be accessible only to the rodents themselves.

Rodents and moles are not the only unwelcome guests in the garden: here’s how to get rid of slugs. As for insects, here you can find out how to eradicate plant pests and eliminate ants.