Does your garden look like a movie set for Attack of the Slugs? Here’s a summary of suggestions for natural ways to keep out the slugs and other garden pests.
The battle is endless. And, for organic gardeners, it’s tougher than ever. Many pesticides are banned under the organic rules (that apply to commercial organic farming). If you’re trying to follow the same guidelines to produce your own crops, you may find that you have a limited artillery in the pest battle. Still, take heart. Natural pest control is all about using what we have. So here are some ideas…
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Organic Slug Control Using Nematodes
The term NEMATODES is an animal classification, covering more than 80,000 species (some of which are present in human beings!). Certain species in this class are parasitic ‐ and it’s these that we are interested in.
Predatory nematodes are a useful weapon in the daily battle against slugs. They’ll eliminate a slug population from the soil; their natural life cycle provides protection for up to 6 weeks. They’re easy to use but fairly expensive to buy. For some crops ‐ like salads and potatoes ‐ or where you’ve had extensive slug damage in the past, this is a good option. But if you’re starting out with pest control, try some less invasive methods first.
Nematodes can be ordered online from good organic gardening catalogues. You’ll need to know how much ground you have to cover before ordering (e.g. 10m³ – 40m³). They will arrive in a sealed container that needs to go straight into your fridge. When you’re ready to use the nematodes, put the required amount into a watering can and top up with plenty of water. Choose a day after, or during, a rain shower. Water the nematodes sparsely over the ground and then follow with another can of plain water to wash them into the soil. The parasites will start acting immediately to protect your crops for around 6 weeks, at which time you’ll need to ensure that you have supplies ready for a reapplication. We’ve found nematodes to be very effective, particularly for potatoes and salads.
For even better protection, why not try a combination of methods? Build a small pond near to your vegetable patch and introduce some tadpoles in the spring. A colony of frogs will do wonders for your slug control – especially when combined with underground predators (nematodes).
Organic Pest Control Using Coffee and Beer
The beer trap is a traditional way of catching slugs. Cut a plastic bottle in half, fill the bottom with a cup of beer, then place the top half, inverted, on top. Bury the trap half‐deep in the soil near your crops, and wait for the slugs to catch a whiff of sweet, sweet beer… Those with a queasy disposition, take note: you’ll have to dispose of the drowned slugs sooner or later.
Another great way to deter slugs is by sprinkling coffee grounds around susceptible crops. Used coffee grounds (from a percolator or espresso machine) are perfect ‐ they’ll dry out thoroughly in the sun, and slugs dislike crossing them. Make your coffee band wide and shallow for the best effect.
Using Flowers as Organic Pest Control
It’s hardly a chore to plant a few rows of marigolds and cornflowers ‐ but these, and similar annuals, have been shown to distract carrot fly from your young crops. Try mixing seed before you sow your lines, blending carrot seed with pot marigold or cornflower (all of which can be sown simultaneously).
Aphids a problem? Interplant with poached egg plant, dill, coriander, helianthus or cosmos ‐ these will all attract lacewings and ladybirds, which love an aphid for lunch.