Slugs are persistent plant-feeders that will feast on the leaves or fruits of just about any plant. They thrive in cool, damp conditions and have the potential to be very destructive, so using a combination of natural preventative measures and DIY treatment methods is key to keeping your harvest safe.
Slugs are small, slimy mollusks that resemble snails without shells. They belong to the Mollusca phylum and are pests for two primary reasons: they leave unsightly slime trails wherever they go (which is usually on your plants and soil) and they eat the leaves and fruits of plants.
Slugs can be tough to spot because they usually come out to feed from dusk to dawn—they don’t like the heat and dryness of the daytime. However, taking a peek at your garden during their peak times to spot the slugs themselves is an easy way to identify them.
If that isn’t an option, look for the goopy white slime and white eggs in your soil first thing in the morning. Of course, you can also look for the telltale shiny slime trails on the leaves of your plants.
As with any pest, prevention is the best and least time-intensive remedy for slugs.
This is a smart idea in general, but is especially helpful in unearthing any overwintering slug eggs and pockets of moisture that might attract slugs.
Copper tape or sheeting is an excellent slug deterrent, as are wood ashes—and the latter is also a nice nutrient supplement for your soil.
There are two approaches to companion planting. The first uses plants that deter slugs around the perimeters of a garden or interspersed with vegetable plants. Garlic and rosemary are strong slug deterrents.
The second uses plants that slugs like more than prized tomato or bean plants so they will (ideally) eat your secondary plants instead. Try marigolds, hostas, or pansies.
This technique only works if you have plants that don’t require constant moisture. However, because slugs are attracted to moisture, those with a persistent slug problem may find it useful not to keep their soil saturated at all times. Instead, only water when the soil starts getting dry, and don’t soak the soil.
Some people also find success by watering only in the morning—that way, the water dissipates significantly by the slugs’ normal feeding time and creates a less hospitable environment.
If you’ve already got slugs, all hope is not lost. Slugs are comparatively easy to eradicate and rarely become so widespread that they can destroy an entire garden. Organic methods are slightly more labor intensive but just as effective as non-organic methods of treatment.
There are also pesticides available to kill or deter slugs, and one of the most popular is a product called “Defender”. These products can be bought in ordinary garden supply stores and come in either a powdered, granulated, or liquid form. Spread them on the affected areas of your garden as indicated by the manufacturer, usually after a rainstorm when many slugs are present.