Diarmuid Gavin: Eco-friendly ways to rid your garden of munching slugs
We're well and truly in the spring gardening season now, and us gardeners are busy sowing seeds and transplanting seedlings, bedding plants, vegetables and herbaceous plants. And, as with any newly-hatched creature on an ominous David Attenborough documentary, the fight for survival now really begins!
Lurking in the long grass, under pots and behind sheds, is an army of creatures, each of whom have up to 27,000 teeth and are waiting to pounce on any fresh green vegetation… with lettuce and hosta top of the menu.
I'm talking about slugs and snails - creatures which instill anger and fear into those of us who want to tame paradise! Due to our mild climate and seasonal lush growth, these tend to be garden enemy number one.
So, if you can't live with them it's timely to consider methods to protect your crops and flowers - there's nothing as disheartening as finding your sweet pea seedlings decimated, the only clue being a tell-tale glistening trail left behind by the molluscs.
But before you march out to wage chemical warfare against these munchers by spraying toxic pellets around the garden, let's remember their value in the ecosystem. They do an important job when they digest rotting vegetation and they are food for hedgehogs, frogs and toads and birds such as the thrush. When you poison a snail, you are also introducing poison to the wildlife food chain. So let's look at the eco-friendly methods of keeping them out:
⬤ Sink plastic containers, such as old yoghurt cartons, into the ground and fill with beer. Ensure a 2cm lip of the container is above ground, which will stop beneficial beetles being lured in for a drop.
⬤ Organic pellets based on iron phosphate are more environmentally-friendly than the traditional metaldehyde pellets. They won't kill other animals and, if not eaten, will be broken down and turned into naturally-occurring iron and phosphate.
⬤ Make slugs' passage to your plants harder with barriers they find difficult to navigate. For example, if you have been pruning roses, these thorny clippings make good barriers and can be removed when the plants have toughened up a bit. You can also use wood ash, grit, crushed egg shells, bark or even cadge used coffee grounds from your local friendly barista.
⬤ Keep veg plots and seedbeds clean of surrounding long grass and other hiding places for slugs, eg weeds and dead leaves.
⬤ Seeds are vulnerable so start them off under cover in a cold frame or greenhouse and then plant out when a bit sturdier. Or you can make mini-cloches for outdoor seeds by chopping an old plastic bottle in half and removing the lid. Not only will it protect against the slugs but it will also act as a mini greenhouse and accelerate germination.
⬤ If your heart is broken every year by slugs shredding your hostas to bits, how about swapping or surrounding them with plants whose fragrance repels slugs, such as astrantia, artemesia, rosemary, rue and fennel. Or try growing hostas in pots with copper tapes - the copper tape deters snails as contact delivers a mild electrical shock.
⬤ Nematodes are microscopic worms that you water into the soil and they enter the slugs and kill them from within. It's called biological control and is considered environmentally-friendly.
⬤ Finally, a night patrol with a torch is a good way of catching pests red-handed. If you decide to relocate them, your neighbour's garden is not a good idea. Not just because it's unfriendly but you need to locate them at least 20 metres away as otherwise their homing instinct will bring them straight back to you!
Water plants in the morning so that surface soil is drier at night, which is less attractive to slugs.