Q What attracts mice to gardens?
A Gardens are ideal habitats for these small mammals as they provide plenty of cover and a wide range of food sources. Sometimes, however, they come into conflict with gardeners when food supplies consist of highly valued plants, seeds and bulbs. When populations peak and food runs short, mice are more likely to become a nuisance in the garden.
Caption: Mice sometimes run into conflict with gardeners
Q Can you tell me more about these animals?
A Mice are small mammals that sometimes feed on garden plants. They are shy nocturnal animals, so there could be more of them in your garden than you suspect. You are most likely to see them when they’re brought into the house by cats.
Rats and house mice are seldom a problem in gardens, although rats may take up residence in compost bins and garden sheds. Dealing with rats is usually a job for the professional – ask your council for help.
Field mice commonly live in gardens, where their vegetarian diet can cause problems for gardeners. For most of the year their numbers tend to remain low. However, in autumn they can build up high populations and cause a great deal of damage into early winter.
Q Could I mistake them for anything else?
A Shrews, unlike mice, are predators which destroy many insects and slugs and so are helpful to gardeners. They have a thin, pointy snout, almost invisible ears, and relatively short tails. They are very small and are mainly active at night.
Q What type of mice am I likely to see in my garden?
A The Long-tailed field mouse (Apodemus sylvaticus) is very active, with large ears, a long tail and, unlike the house mouse, a white underside. The adults are 9-12cm long, including their tail. You sometimes find their underground burrows in the garden, lined with leaves and containing winter food stores of seeds and grain. Long-tailed field mice prefer to live in hedges, shrubs and around trees. They breed all summer and don’t hibernate in winter.
Q What damage is caused by mice?
A Seeds are often eaten by field mice, especially pea and bean seed that is sown when mice are numerous in the autumn, or when food is short in the spring. They will invade the greenhouse to carry off newly sown seeds from seed trays. The seeds of trees are also often eaten by field mice and voles, but this is usually helpful to gardeners, as it prevents large numbers of unwanted seedlings from appearing.
Bulbs, corms and tubers may be consumed by field mice, especially newly planted ones. They like tulips and crocuses in the autumn. Fruit and vegetables may be taken by mice.
Q Don’t mice do some good too?
A They are important food for owls, foxes and other wildlife, so unless they are troublesome, they should be left alone. Mice also eat insects and weed seeds; in this respect, they are helpful to gardeners.
Q What can I do to deter them?
A Seeds and bulbs can be started off indoors in pots, to avoid the attentions of mice. Fine mesh wire netting (6.5mm) and a sound concrete floor can exclude them from the greenhouse.
Outside, wire netting placed over buried bulbs and seeds can protect them. It can also be wrapped around tree stems and buried slightly to guard tree and shrub stems from gnawing. In extreme cases, trapping can be carried out. Bait the traps with peanut butter or sausage roll for mice. Cover traps with a cloche or propped-up seed trays so birds and pets are not hurt by accident.
Live-capture traps, where the animals are taken alive, can also be used. The traps must be checked every day, and trapping has to be carried on for a long period, as empty sites are soon recolonised by mice moving in from elsewhere. For this method to be effective, you have to release the trapped animals at least half a mile away, or there is a good chance they will make their way back.
Some gardeners maintain that holly leaves or gorse sprigs scattered along seed rows will deter mice from digging up seeds.
Q Can I poison them?
A No. Poisoning in the garden could present far too high a risk to pets and wildlife. Careful trapping and preventative measures should be enough to limit damage.
Q Are there dressings I can use to protect my seeds and bulbs?
A The old remedies involving poisons like lead are no longer allowed and, in any case, are very risky for the gardener to use. There are no safe, effective modern substitutes.