Slugs are the bane of gardeners’ lives, regularly topping surveys of garden pests. They munch the new growth of precious plants, demolish seedlings overnight and munch irregularly-shaped holes in leaves, stems, flowers, tubers and bulbs and potatoes, leaving their silvery slime trails behind.
Slugs are active for most of the year but are a particular problem in spring, when there’s plenty of young growth for them to eat. They are mostly active after dark, especially when it’s warm and damp. In hot, dry weather they bury themselves in the soil or hide in cool, dark places to avoid dehydrating.
There are over 40 species of slugs in the UK. Not all slugs eat live plants, however – many of the larger ones eat decaying or dead plant material and they are an important part of the composting process.
Despite your best efforts, some losses to slugs are inevitable. Accept that your garden is never going to be slug free, and find ways to work around this.
Make sure you prioritise the protection of the most vulnerable plants – all seedlings, new growth on most herbaceous plants, and all parts of especially susceptible plants such as delphiniums, hostas and dahlias. If you’re growing plants in pots, make sure there isn’t a ‘bridge’ of leaves from one plant to another, as slugs can travel from pot to pot this way.
Sow extra seeds so you have seedlings waiting in the wings to replace any that are eaten by slugs, and grow more than you need so you still have some crops left over after a slug attack. And add plenty of slug-resistant plants (see our list below) to keep damage to a minimum.
There are many options for controlling slugs. The best approach is to combine several methods, starting early in spring. Here are some ways to controlling slugs in your garden, some of them recommended in a survey of readers of BBC Gardeners’ World Magazine.
Slugs can be a major nuisance in gardens, especially for delicate plants like basket grass While chemical pesticides may seem like an easy solution, they can be harmful to pets, children, beneficial insects and worms in the soil Thankfully, there are many effective organic methods to get rid of slugs without resorting to toxic chemicals.
Why Slugs Love Basket Grass
Basket grass (Oplismenus) is an attractive ornamental grass prized for its arching green leaves However, the broad, soft foliage makes it irresistible to slugs and snails These slimy mollusks use rasping tongues to chew holes in plant leaves and stems. Their feeding damage quickly ruins the ornamental value of basket grass.
Slugs thrive in the moist shady conditions preferred by most basket grass varieties. The lack of air circulation allows slugs to travel safely to plants. Heavy mulch and dense groundcovers used in basket grass landscaping also provide slugs with ample hiding spots near their food source.
Organic Ways to Control Slugs on Basket Grass
Remove Hiding Spots
Eliminate excess mulch, weeds, boards and debris near basket grass plantings. This forces slugs out into the open where they are more vulnerable. Rake mulch away from the base of plants. Prune away any low-growing leaves in contact with the ground. Improving air circulation dries out their habitat.
Use Iron Phosphate Slug Bait
Sprinkle iron phosphate pellets around the perimeter of basket grass plantings. Iron phosphate occurs naturally in soil and is not toxic to people, pets or wildlife when used as directed. It is approved for organic gardening. The abrasive pellets dehydrate slugs when ingested. Apply after watering or rain so bait remains effective. Reapply as needed after heavy rain.
Try Diatomaceous Earth
Spread diatomaceous earth, a powder made from fossilized algae, on top of soil around basket grass. The sharp edges cut and dehydrate slugs. Avoid breathing in the dust when applying. Reapply after rain or overhead watering. Use food-grade diatomaceous earth for safety. Wear a mask when spreading to avoid inhaling the fine powder.
Set Out Beer Traps
Bury shallow containers of beer flush with soil around plants. Slugs are attracted to the yeasty odor but drown when they fall in. Avoid trapping beneficial insects by placing traps under boards raised off the ground. Or use milk jugs with part of the bottom cut out and buried. Discard and replace trap contents frequently.
Encourage Natural Predators
Welcome birds, snakes, toads, frogs, beetles and fireflies to your garden with habitat for them like brush piles. They will help control slugs and other pests. Avoid pesticides that kill beneficial predators. Keep a birdbath full of fresh water. Install owl or hawk boxes to encourage insect-eating birds.
Block Slugs with Copper
Ring basket grass with copper tape or mesh with the shiny side facing out. Slugs receive a mild electric shock from copper that deters them. Bury edges in soil so slugs cannot go under. Copper bands can also be wrapped around planting boxes or pots. Replace copper strips yearly as needed since copper wears off.
Use Caffeine Sprays
Spray a mixture of caffeine and water directly onto slugs and infested plants. The caffeine absorbs through their skin and kills them. Use coffee grounds from brewed coffee or purchase pure caffeine powder. Mix 1-2 tablespoons per gallon of water. Test on a small area first in case of plant sensitivity. Reapply after rain.
Grow Slug-Resistant Plants
Interplant basket grass with slug-resistant flowers like geraniums, lavender, foxglove, iris, dianthus, alyssum, salvia or osteospermum. These plants seem to repel slugs with their fragrances or fuzzy leaves. Low-growing thyme is also rarely bothered by slugs. The aromatic leaves emit essential oils slugs avoid.
Check Plants at Night
Go out after dark with a flashlight to handpick slugs off plants. Catch them in a plastic container or dump into a pail of soapy water. Crush larger slugs or cut them in half for instant death. Inspect undersides of leaves and inside curled foliage where slugs like to hide during the day.
Protect Young Shoots
Cut plastic bottles or soda cups in half and place over freshly planted basket grass until it is established. Or wrap aluminum foil around the base of grass clumps to block slugs. Remove barriers once plants are large enough to withstand some feeding damage on outer leaves.
Prevent Slugs from Returning
- Keep garden debris cleaned up and avoid over-mulching
- Eliminate mossy, overly damp areas
- Allow soil to dry between waterings
- Turn over soil to expose slug eggs and juveniles
- Rotate bait types to prevent resistance
- Check for hitchhiking slugs on new plants
- Inspect under boards and in compost piles
- Handpick daily to control populations
With persistence and multiple control methods, you can protect basket grass from slug damage. Always follow organic product labels carefully and take safety precautions when using baits. Focus on making the environment less hospitable rather than wiping out every last slug. A balanced garden ecosystem keeps pest problems in check naturally.
Use organic slug pellets
Slug pellets that contain metaldehyde kill slugs, but they also kill the animals that eat them, such as birds and hedgehogs. They have now been banned as a result. Sales of metaldehyde slug pellets ended in March 2021 and stocks must be disposed of by 31 March 2022. Pellets made from ferric phosphate are just as effective but are apparently less harmful to wildlife and are approved for use by organic growers. Scatter the pellets on the soil as soon as you can before tender young growth appears. Bear in mind, however, that if you scatter them liberally, you will ultimately get fewer predators coming to eat the slugs in your garden – leaving you reliant on pellets. Therefore use the pellets sparingly, around particularly susceptible plants, for example.
- Buy organic slug pellets from Amazon, Gardening Naturally and Waitrose
How to control slugs
Ultimately, the best thing you can do to control slugs in your garden is to create a healthy ecosystem. Create lots of habitats for slug predators – hedges, shrubs (especially those with berries) and trees will all attract birds such as blackbirds and thrushes, which eat slugs (and snails). If you have room, a wildlife pond is a great addition to your garden – the newts, frogs and toads that use it will also devour slugs. Laying a slat down will attract slow worms, which eat a lot of slugs. Encourage wildlife in to your garden by creating a small hole in a fence so frogs, toads, slow worms and other species, such as hedgehogs, can travel freely between your plot and neighbouring ones. Create a log or leaf pile, or a large open compost heap, where they can make a home.
Healthy soil produces healthy plants that are much more able to withstand slug damage – slugs tend to attack plants that are already weakened in some way. So mulch your garden with homemade compost, composted green waste or well-rotted manure to support healthy soil. If you don’t make your own compost, check out our comprehensive guide to getting started, which also includes a roundup of the best compost bins to buy.
How to Stop Slugs Eating Your Plants (100% Organic)
FAQ
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