A gardening expert has shut down the idea that using eggshells and coffee will do much to protect your plants from slugs. Instead, they suggested a different homemade device entirely could make more of a difference.
Expert Claire Ratinon was debunking popular gardening tips when she remarked on whether using coffee and eggshells is the best way to shield your garden from damage caused by slugs.
Admitting it was the question most people asked her, she recommended a different approach entirely. What’s more, the method she suggested is one people can try at home, by creating the beer trap device Claire discussed through a few easy steps.
Writing in the Guardian, Claire said: “How to manage slugs is my most-asked question, even though the Royal Horticultural Society has stopped describing these molluscs as pests, and says that only nine of the estimated 44 UK species of slug are ‘notable plant nibblers’.
“In my experience, coffee grounds and eggshells do little to protect plants. Beer traps do work in that they coax slugs into a yeasty, watery grave, but they require monitoring, emptying and refilling, which is not a pleasant task. How effective they are depends on how many you put out and the size of your slug population.”
Whilst it is possible to buy bespoke beer traps, they can also be made without any additional cost by using common household items. Better Homes & Gardens say it is possible to make your own with “old yoghurt or cottage cheese containers that are at least four inches deep”.
When it comes to the beer, no specific brand or strength was mentioned, but the website did suggest erring for cheap versions of the drink.
They added that once the container has been identified, gardeners should add just three inches of beer into the cup, because too much booze will allow the slugs to escape.
They explained: “Add about three inches of beer to the container. Don’t fill the container all the way–it will take a lot of beer and make it easier for the slugs to escape.
“A freshly baited slug beer trap will remain effective for 2-3 days. After that, the odor of the beer is gone, and so is the slug-attracting ability. Empty out the dead slugs and re-bait the traps with fresh beer.”
Whilst coffee grounds may not be considered effective for fighting slugs by some, others have stuck by the theory, including the gardening blog Tea and Coffee, which has claimed coffee could be a deterrent. It’s not because slugs are snobbish about arabica verses robusta, but because the grounds are actually poisonous to them.
The blog said: “Coffee grounds contain a chemical called alkaloid, which is poisonous to slugs. When slugs ingest coffee grounds, they suffer from severe dehydration and eventually die.
“For these reasons, slugs will avoid areas where coffee grounds have been sprinkled. While coffee grounds may not be the most effective way to keep slugs out of your garden, they can be a helpful tool in deterring these pests.”