Dealing with Pests: Slugs and Root Maggots

It’s slug season! With organic gardening, pests are going to happen, and two that have shown their little pesky faces this season are slugs and root maggots. You may recognize the familiar munching of slugs, leaving holes in your leafy greens.


There are a few methods to deterring slugs. First is Sluggo, which is a slug-killer that is certified for organic use. If you have pets you might want to avoid this, as it can be harmful if consumed in large quantities.


The second slug catching method is the Slug Pub. In this popular method, you catch slugs by luring them with beer. Check out this link to find out how to do it!


The grapefruit method is a method for all you citrus lovers. After eating a grapefruit half, place the rind face down in your garden. The slugs will be attracted by the moist environment among the rotting peel and crawl underneath. Check the grapefruit frequently and toss any slugs you find in the trash or in a bucket of water, or toss the grapefruit completely. You might need a few grapefruits around your garden, as they don’t have the widest range.


Finally, you can deter slugs by spreading something scratchy like diatomaceous earth or crushed eggshells around your garden, these materials irritate the slugs, keeping them out.

Root maggots are a little bit more difficult to pinpoint. Flies lay their eggs at the base of a plant, and when they hatch, tiny worms burrowing around the roots of brassicas (cabbage, broccoli, cauliflower, kohlrabi, radishes, brussels sprouts, kale). Above ground, the plants will appear upright and alive, if a little stunted, but the lower and outer leaves may be colored red or yellow. This might be mistaken for a nutrient deficiency, but below the surface the roots may be eaten away. If your plant topples over, or you gently tug on the plant and it pops right out the soil due to lack of root material, it is likely that root maggots are the cause. You might be able to find a few little white worms in the soil beneath the plant.


In root crops like turnips or rutabagas, the root might be salvaged and the damaged portion cut away. Above ground crops are also often able to be saved, but your cauliflower and kohlrabi might be quite small. It is important to dispose of infected plants quickly, but don’t put them in your compost bin!

To avoid root maggots, it is a good idea to not plant brassicas too close together. Inter-planting with smelly herbs or flowers like cilantro or marigolds will also deter the pests. You might try spreading a layer of diatomaceous earth or wood ashes, or a waterproof or cotton disc around the base of your plants to avoid having the flies lay their eggs in your crops. Or you can cover your garden with row cover fabric after planting as a physical barrier. If you already have root maggots in your soil, it is a good idea to rotate your crops year to year, switching up where you plant your veggies. If you need to remove damaged plants mid-season, try planting a non-brassica leafy green there. By mid-July there is still time to get a crop of lettuce or chard from seed!

Questions? Contact us any time.