Sophie Valentine posts pictures of her stunning garden and the tips she uses to make it look so beautiful on her Instagram account @lookinsidemygarden.
They target young slugs, living under the ground, and so are very effective.
Nematodes can be bought online and come looking like dry yeast.
To use them, sprinkle a packet of nematodes into your watering can and water wherever you would like them to be effective.
Nemaslug claims to provide 300,000 nematodes for every square metre of soil and will protect from slugs for six weeks.
One victim of slugs, dahlias, are among the most popular summer flowers.
However, they can be “extremely sensitive”, one gardener has warned.
Now, how to grow dahlias to produce stunning flowers has been detailed by the gardener.
Lizzie, behind The Rose Press Garden, said: “Dahlias are beautiful and a ‘must-have’ in any sunny spot in the garden.”