Hartley Magazine

All the latest news, hints, tips and advice from our experts

Tips for Pest and Slug Control

It’s not only plants that are active at this time of year, the pests that thrive on them are increasing too as there is more and more to eat. Top of the list are slugs which delight in munching their way through the soft young growth that’s encouraged by sunshine and April showers, they’ve even sneaked into the greenhouse too!

One of the best ways to control slugs is using naturally occurring nematodes which are watered into the soil; it’s quite expensive, but effective and they harmful to animals. The soil should be moist and at a temperature of 5-20 deg C when they are applied so they are at their most effective in spring and autumn. Several treatments may be needed when plants are in active growth. Another method is to use ‘beer traps’ with stout and non-alcoholic larger the most effective baits these can be bought from garden centres or made from a jam jar. Make sure that they are buried so the rim is slightly proud of the soil level so they don’t trap garden predators like ground beetles and make sure that a small stick with its base in the beer is leaning against the side so they have a ‘ladder’ to climb out. Halved hollowed, grapefruit or orange skins can be laid flat edge down, sheets of plastic or hessian, old lettuce leaves or any vegetation which makes a tasty meal or is moist underneath can be used as a trap. Check them daily, preferably in the morning and remove the slugs your victims. Gardeners devise their won methods of killing them, from sprinkling them with salt, putting them in a bucket of salt solution or disposing of them on waste ground to more gruesome methods like cutting them in half with secateurs!!

Protect transplants with plastic collars 2-3” tall cut from sections of plastic drinks bottles, make sure there are no slugs around the plant before putting the collar in place or you will trap them inside rather than out!

Place copper barriers around plants or copper tape around pots or use of moisture absorbent material which acts as a physical barrier that they cannot crawl over. There is plenty of choice at garden centres.

Go slug picking on warm, damp evenings and hand pick them into a container or use a pair of tongs to pick them up. Natural predators like frogs, toads, hedgehogs, slow worms and ground beetles are effective too, they can be encouraged into the garden by building a log pile for them to live in. Birds also eat slugs eggs if the ground is turned over and raked winter.

Finally, there is chemical control. Pellets may harm wildlife, pets and children if eaten in volume, so always follow manufacturer’s instructions; most gardeners spread slug pellets too thickly. Use liquid or pelleted forms of metaldehyde or pellets based on aluminium sulphate and ferrous phosphate which are less toxic to other animals. The most vulnerable plants are those which are yet to become established, once they are robust enough, most tolerate slug damage but it is unsightly and unwelcome on ornamental plants. Good luck!