FAQ: Pest Control in a Wildlife Garden

Controlling pests in a wildlife garden is an age-old problem. Just how do you keep those one or two voracious nuisances at bay without simultaneously wiping out the whole gang of their relatives that you’re really rather keen to encourage?

It’s not an easy balance to strike, but with a bit of thought, principally about prevention, the good news is that it can be done without resorting to pesticides.

How Can I Prevent Pests Becoming A Problem In The First Place?

When it comes to pests, that old proverb about an ounce of prevention is so true! Stopping pests getting a hold in the first place is always a good idea, but doubly so for the wildlife gardener. The most straightforward way of doing this involves preventing them from getting to their intended targets – but that’s obviously a good deal easier said than done.

Some kinds of plants can be protected physically – grown under cloches for instance – while some pests, such as slugs can be kept away by sharp gravel or copper rings around the base of the plant. These kinds of methods aren’t appropriate for everything, but where they are, they can be very effective.

Natural, non-pesticide repellents can also sometimes be helpful. Cedar-wood chips and citronella oil, for example, can be used to keep insects away from particular areas and many people have found them especially effective at warding off mosquitoes and other biting insects that can be such a plague on summer evenings. Mint is another old country remedy that some gardeners swear by – grow it in your garden, or pack around any bulbs or seeds that you’re storing, and it’s said to keep the mice away.

What Plants Can I Grow to Keep Pests Away?

Generations of gardeners have grown pyrethrum to benefit from the natural insecticide it gives off, using it to protect other more vulnerable plants. It has a place in the wildlife garden, but it’s important to remember that although it’s “natural” it’s still pretty potent and will deter all kinds of insects, not just the pest species, so where you plant it needs to be thought out carefully.

Other plants which are said to be useful in keeping pests away seem to be more selective. Sage, thyme and rosemary, for instance, are supposed to combat caterpillars, wormwood and rue keep down ticks, while aphids seem not to like members of the onion family.

What Kinds of Insect Are Good For Pest Control?

The number one insect “good-guy” has to be the ladybird – each one happily munching through a huge number of aphids over its lifetime. The slightly less well known lacewing, at least as a larva, is another champion aphid-eater, as well as having a voracious appetite for a range of small caterpillars and insect eggs in general.

The contribution of many other kinds of helpful bugs often goes largely unrecognised and the identities of some of these unsung heroes may surprise you. Wasps and hornets – although often seen as nuisances in their own right – consume large numbers of caterpillars and insect pests, while the fearsome-looking Devil’s Coachman has a real taste for slugs. Many common ground beetles share the Coachman’s love of slugs, adding weevils, leatherjackets and chafer grubs to the menu, and any hover flies you see in your garden will be doing their bit to keep aphids from getting completely out of hand.

How Can I Control Slugs Without Using Slug Pellets?

Gardeners need no reminder of the ravages that slugs can wreak on young, tender plants, but for the wildlife gardener the traditional slug pellet remedy is an obvious non-starter. Fortunately there are other ways to deal with the mollusc menace.

As mentioned above, sharp sand and copper rings can help to keep the little blighters away, while some gardeners find wool shoddy – a by-product of the textile industry – makes a great natural slug deterrent. The added bonus of this approach is that shoddy also has a good reputation as a slow release nitrogen fertiliser. Although you once needed a friendly sheep farmer or a local woollen mill to get the stuff, these days it is conveniently packaged and purpose-marketed for the job.

The state-of-the-art in pesticide-free slug control, however, involves biological control, using a pre-packaged nematode worm available from many garden centres and by mail order suppliers. You simply need to make up the solution in your watering can and then water these microscopic creatures into the soil – the nematodes will do the rest. Highly specific, they only target slugs, passing on a lethal disease that doesn’t infect any other kinds of creatures and allowing your hostas to thrive without having huge chunks chewed out of them!

Pest control presents a few challenges for the wildlife gardener, but with care and forethought it is possible to meet the needs of the wild creatures you’re pleased to see, without having to put up with too much damage from those that aren’t so welcome. It’s always going to be impossible to be entirely pest-free, so you’re bound to see the odd chewed stalk, but don’t forget that any unwanted bugs you do have will probably make the perfect meal for something you be happy to have visit.

Nature is nothing if not balanced!

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