The Problem: Snails and Slugs in Marijuana Garden
Symptoms: Plants chopped down; slimy trails all over the outdoor garden.
Solution: I’ve eaten snails, and that’s the way I prefer them: on my plate rather than on my garden plants. People feel the same way and somebody related the story of a marijuana grower friend who innocently placed his indoor marijuana plants in the late-spring garden in his backyard. The friend moved six young plants barely six inches tall into the yard in small pots, intending to transplant them the next day. But when he went out to take on that task, all that was left of the plants was the stub of a stem—and the slimy trails left by snails. This will not happen in the indoor garden, but snail or slug damage is a problem outdoors.
These pests can be controlled, of course, but don’t poison them. Snail and slug bait containing metaldehyde or methiocarb have killed countless thousands of domestic pets and birds as well as beneficial insects and earthworms. Iron phosphate is considered to be a “safe bait,” but I have an aversion to spreading any kind of poison. People shudder at the thought, so it’s another reason for building an urban garden that’s a barrier against them. It’s much better to creatively deter snails and slugs
Barriers, traps and other techniques: Snails and slugs are copper-phobic— the slime of snails and slugs reacts with copper and this repels them. You can create barriers around your plants with scrap copper, or buy self-adhesive copper tape to wrap around the rims of the pots. These copper-phobic mollusks are also beeraholics—I’m not kidding. If you place beer in a shallow dish, you can trap them easily and recycle them if they’re not eaten first by starlings, which love them marinated in Miller Lite. Some master gardeners recommend an ingenious solution of spraying weeds with beer so the snails will eat them. Also, try planting “repellent” species—like lavender, thyme, sage, mint, and geraniums—that the slugs and snails hate.
Rough mulch can also be an effective barrier, so even if the marijuana plants are in pots, surround them with crushed eggshells, pine needles, straw, or the bark sold in garden stores for mulching. While you’re doing that, you can make simple traps in the yard, such as upside down plant pots and wooden boards where snails and slugs hide and breed. Also, check regularly under rocks, logs, and any thick vegetation you have in your garden. If you find any and don’t want to touch them, use tongs to throw them into a bucket of soapy water, where they will be unable to climb out and soon drown. You can just recycle the dead pests into the compost pile. Since snails and slugs are most active at night and like moisture, water in the morning so the top of the ground will dry out by evening; dry ground will harbor fewer of these mollusks.
Finally, introduce some slug predators into your yard. A surprising number of domesticated animals eat them, including dogs, cats, ducks, and chickens, so they would be likely candidates for controlling the slimy ones. Just one note of caution—ducks and chickens eat vegetation, too. A fellow marijuana grower reported that a slug predator has moved into his yard, built a nest under his gas grill out of bamboo leaves, and is eating every slug he can find. It’s a European hedgehog (Erinaceus europaeus) he named Schneckenfresser (“slug-eater”).