Garlic could be the new way to drive slugs away from our lettuce without using pesticides.
By Kristine Krug, in Salford
The smelly herb not only seems to keep vampires at bay, but scientists say it also drives slugs and snails out of the garden.
Slug protection costs £30m a year in the UK
Biologists from the University of Newcastle, UK, have found that a barrier of garlic oil repelled the molluscs.
Dr Gordon Port, who heads the research project, described at the British Association's science festival in Salford, Greater Manchester, how exposure to refined garlic can even kill slugs.
Garlic has been co-planted as an anti-pest control for hundreds of years.
Dr Port's experiment now shows that an experimental refined garlic spray called Ecoguard can effectively deter slugs. It is not yet clear how garlic exerts its repulsive effect.
But Dr Port described how prolonged exposure can kill the slugs: "They show an overproduction of mucus. They seem to dry up."
He suspects the oil damages the creatures' nervous systems, but he is not entirely sure how.
After the laboratory results, the garlic oil now needs to be tested in the field.
"We want to find out how garlic affects other creatures living in the soil, the right concentration to use, how it affects the taste of food and many other things," Dr Port said.
Keen gardeners might not have to wait for test results.
"You could try to make it up yourself," he said.
As a common cooking ingredient it should be safe to use but the tricky bit is to work out the right concentration of garlic.
As more and more pesticides were withdrawn from sale, this common cooking ingredient might pose a viable, eco-friendly alternative, Dr Port said.
An estimated £30m a year is spent in the UK to protect lettuce, Brussels sprouts, potatoes and winter wheat from slugs and snails.
"Pesticide have been terrific at preventing pests and increase food availability."
But amid growing awareness of their potential dangers, the number of pesticides available to gardeners and farmers had gone down in recent years, he explained.
Many products that were not entered into the European Union review of pesticides which began in 1995 were withdrawn from sale in the UK on 24 July this year.
Now the hunt for effective and bio-friendly alternatives is on.
"We need to find new environmentally friendly and cost-effective ways of controlling molluscs, and garlic could be our answer," said Dr Port.