How to keep slimy pests at bay
Even if we’ve lost a few flowers and had to deal with soggy lawns, the rain has been wonderful for the garden, setting established trees and shrubs up for the summer ahead and giving new plantings a good start.
It’s also just what snails and slugs like to get going – and going. Snails and slugs (collectively molluscs) relish moist conditions to help them slime their way to eat your plants.
Signs of snail attack include chewed leaves, seedlings that disappear overnight, and silvery trails. When times are dry, they hibernate among rockwork, under pot rims and in hidey-holes waiting for a rainy day.
Controlling snails takes a multi-pronged approach. When numbers are high and particularly when the plants are valuable, don’t muck about. Scatter pellets of organic, iron-based snail bait (iron phosphate) to quickly and efficiently reduce pest numbers. Iron breaks down safely in soil although EDTA formulations can harm earthworms.
Avoid baits based on metaldehyde or methiocarb, which are highly toxic to pests and wildlife. Snails poisoned by these baits can pass the poison down the food chain. These baits are also highly attractive to dogs. Some toxic baits include a bittering agent that makes them unappealing to pets and therefore safer but they still rely on a highly toxic bait to kill snails.
TRAPS AND HUNTS
As well as using snail bait, experiment with snail traps and natural baits.
Beer traps are much loved by gardeners and snails. What a great excuse for a beer: “I’ve got to top up the snail trap so I may as well open a can!”. Yeast-based dough balls are even more attractive to snails and lasts for up to eight days at a time.
Trap snails by sinking a saucer or a commercial snail trap containing bait into the soil. Snails also hide under cardboard, newspaper or orange skins so combine these materials with dough baits. Collect up and kill the snails you’ve trapped.
Don’t just throw them over the fence – snails come back!
Follow up baiting with regular snail patrols. Snails are most active at night, especially on wet evenings, so before you head to bed is the best time to hunt for snails.
Also check in the morning, for any stragglers.
At night, take a torch to help spotlight snails, slugs and their slimy trails. Look under foliage and around the edges of pots and garden beds.
Pay particular attention to new seedlings, leafy vegetables, emerging bulbs such as liliums, dahlias and hostas.
Dump the collected snails in a bucket of soapy or salty water as an alternative to treading on them.
When the snails are dead, they can be buried in the garden as fertiliser.
As well keeping an eye out for common snails which come in a range of sizes, check plants, soil and garden mulch for small conically shaped snails. Despite their small size, these snails can do a lot of eating. They are easy to miss so keep watch for these pests too.
Caffeine is also toxic to molluscs. A weak spray made of black coffee and water can protect plants but it is easily washed off and some plants are sensitive to caffeine as well so take care with this option.
Unfortunately, the caffeine in coffee grounds doesn’t seem to be an effective deterrent. Snails manage to crawl over these – along with sand, sandpaper and crushed eggshells – in pursuit of tasty plants.
Finally, don’t think that’s the last you’ll see of snails. They’ll bide their time and return when you stop being vigilant. Snails can lay 50-100 eggs so there’s an army of new snails just waiting in the wings.