Slugs and Snails – Garden Pest Control
Slugs and Snails
(Deroceras reticulatum, Anion hortensis, Anion ater, Milax spp. And Helix apsera)
There are many slugs ranging in colour from pinkish-fawn to black. The majority are approximately 3-4.2cm (1-¼ – 3-3/4in) in length, although one species grows up to 15cm (6in).
Typical symptoms include seedlings eaten or failing to come up and irregular holes in roots, stems, bulbs, tubers, fruit and leaves of many plants. Damage is usually worse in warm, damp conditions, especially in spring and autumn.
Look out for characteristic slime trails to confirm diagnosis or go out into the garden at night and see them.
There is no single simple method of dealing with slugs and snails. The best you can aim for is to reduce their numbers and to protect plants as long as they are vulnerable.
Prevention and treatment
• Encourage natural enemies, including frogs, toads, birds, beetles and centipedes.
• Ensure quick germination and growth of seedlings. Never sow or plant into cold.
• Use sturdy, vigorous transplants that have been grown in modules or pots.
• When sowing seeds, water the bottom of the drill then cover with dry soil.
• Water transplants in the morning so there is no film of water left on the soil or leaves by the evening.
• Where snails are a particular problem, do not plant vulnerable plants near walls covered with ivy or other climbers, piles of logs and other similar situations where snails may lurk.
• Grow varieties of potato less susceptible to slugs; harvest all tubers by early autumn.
• Soil dug in the autumn allows slugs to move down into the soil to hibernate. If you must dig, do it in the cold of winter for maximum disruption of slugs and eggs.
• Protect seedlings and young plants with plastic bottle cloches.
• Remove slugs from areas of new seedlings or transplants. Slugs will congregate under roof tiles, lettuce leaves, wet newspaper or a pile of comfrey leaves laid on the soil; they can then be collected up and disposed of as you see fit. It is worth starting this before plants are introduced into the area.
• Lay a continuous ring of comfrey leaves around an area of susceptible plants. This seems to act as a decoy, but is said to be ineffective after mid-summer.
• Go out at night with a torch and remove slugs and snails from plants.
• Use slug /traps in areas of new seedlings and transplants.
• Use a method of biological control.