Slug and snail infestations in a garden can cause significant damage to plants and be a nuisance for gardeners. These mollusks feed on the leaves, stems, and fruit of plants, leaving behind holes and chew marks. They also produce a slimy trail as they move, which can be unsightly and can harbor fungal growth. Infestations can lead to wilted, stunted plant growth, and in severe cases, the loss of seedlings and young plants. Gardeners should regularly inspect their plants and soil for the presence of slugs and snails, as well as their damage, in order to prevent or mitigate infestations.
While slugs and snails may look different, they can cause similar damage and have similar habits in a garden.
Symptoms
- Significant damage to leaves, including large holes and entire leaves that have been consumed
- Stem damage, with stems chewed or cut through completely
- Damage to flowers, including chewed petals and destruction of entire blooms
- Destruction of seedlings and young plants
- Slugs and snails feed both at night and during the day, and their feeding can often leave behind slimy trails or feces on the leaves and stems of plants
- In severe infestations, there may also be an accumulation of dead snails and slugs, as well as discarded shells.
What is a Slug or Snail
Appearance of Slugs:
- Soft, cylindrical body with a distinct head and tail
- Can range in size from a few millimeters to several inches long
- Single, broad, foot-like sole to help them move along surfaces
- Two retractable eye stalks and a mouth located at the front of their body
- Brown, gray, green, or black in color, with some species having stripes or spots
- Secrete a thick, slippery mucus to help them move and protect their skin
Appearance of Snails:
- Soft, coiled shell on their back, with a head and tail extending from the opening of the shell
- Shell can range in size from a few millimeters to several inches in diameter
- Single, broad, foot-like sole to help them move along surfaces
- Two retractable eye stalks and a mouth located at the front of their body
- Shell can be brown, gray, green, or yellow in color, with some species having stripes or spots
- Secrete a thick, slippery mucus to help them move and protect their skin.
Treating a Slug or Snail Infestation
It may be necessary to use multiple methods to effectively control a slug or snail infestation in a garden. For example, using slug and snail bait in combination with manual removal and barrier methods can provide a more comprehensive approach to controlling pests.
Manual removal
- Check the garden at least once a day, especially after rains or watering
- Look for slugs and snails on the leaves, stems, and soil surface of plants
- Remove any pests you find and dispose of them in a compost bin or discard them away from the garden
- Consider using a flashlight at night to help you spot slugs and snails more easily
Use of Slug and Snail Bait
- Apply the bait evenly and in a thin layer, following the instructions on the package
- Place bait near the plants and along the soil surface, especially in areas where slugs and snails are known to be active
- Bait can be reapplied after rains or watering, as the product may become dispersed or diluted
- Do not place bait near plants that are attractive to pets or wildlife, as the bait can be toxic to them
- Be careful not to spill the bait, as it can harm other plants and the soil
Barrier Methods
- Cut copper strips or mesh to the desired length, making sure to leave enough to extend above the soil surface
- Place the copper strips or mesh around the base of plants, pots, or garden beds
- Make sure the barrier is in contact with the soil and is not obstructed by leaves, stems, or other objects
- Be aware that copper strips and mesh can become less effective over time as they become covered in organic matter or patina
- Copper mesh or strips can be cut to size, making it possible to use them around small pots or individual plants
Encouraging Natural Predators
- Provide bird feeders with food and water, especially in the spring and summer
- Provide nesting boxes or bird houses for birds that feed on slugs and snails
- Attract toads and ground beetles by providing moist areas and hiding places, such as rocks and wood piles
- Consider planting native flowers and shrubs that attract beneficial insects and other wildlife to your garden
Cultural Control Methods
- Remove leaf litter, grass clippings, and other organic matter from around plants and soil surfaces
- Keep soil surfaces dry, especially in the evenings and at night, when slugs and snails are most active
- Use drip irrigation or water plants early in the day, allowing the foliage to dry out before night
- Consider planting resistant species or varieties, such as herbs and vegetables with tough leaves or flowering plants with stiff stems
- Avoid using high-nitrogen fertilizers, as they can encourage lush, tender growth that is more attractive to slugs and snails.