Why surrounding plants with crushed eggshells won’t prevent slugs

There are tips that I come across at least once a week while gardening. The idea is that if you place a ring of crushed eggshells around your plants, you’ll create an effective natural barrier against slugs and snails. With more and more gardeners keen to avoid using pesticides, could this age-old advice be more relevant than ever for home growers? Let’s look at the science.

This is how it works. The sharp, rough edges of crushed egg shells…