The best organic slug bait to kill garden slugs and snails. Stop slug damage now with safe bait that can be used around pets and wildlife.
Slugs and snails are devastating to the garden. Their bacteria-infested slime is harmful to plants and even a danger to humans as we’ve seen with Hawaii’s rat lungworm disease endemic.
There are many organic ways to control slugs and snails in the garden from using beer cans as a trap, to laying down copper foil tape, ash, or diatomaceous earth around plants. In this article, we review one of the most effective methods to eliminate slugs and snails—slug bait.
What is slug bait made from?
Slug bait is usually sold as granular pellets with 1–6% active ingredient (slug killer) and an inactive cereal bran base or wheat gluten. Most organic slug bait contains iron phosphate as the active ingredient to kill slugs and snails.
Organic Slug Baits
Iron Phosphate Slug Baits
Active ingredient: Iron Phosphate 1%
The naturally-occurring substance iron phosphate has been the most prevalent active ingredient used in organic slug bait pellets for the past decade. Iron phosphate is Generally Recognized As Safe (GRAS) by the Food & Drug Administration (FDA). Iron phosphate has low water solubility and is considered a safer alternative to non-organic slug baits containing Metaldehyde.
Both Sluggo and Sluggo Plus are OMRI certified organic slug bait pellets that use 1% iron phosphate as the active ingredient, the difference being Sluggo Plus adds spinosad (explained below).
How it works: Iron phosphate slug bait takes 3–7 days to kill slugs and snails. Slugs and snails often stop feeding on plants after ingesting iron phosphate slug bait, although it can take as long as a week for them to die. The low water solubility of iron phosphate gives these slug bait pellets longevity in rainy areas.
Best Organic Slug Baits with Iron Phosphate
Sluggo
Sluggo Slug Bait: Kills Snails & Slugs
Active ingredient: Iron Phosphate 1%
If you have a slug or snail problem in the garden, one of the best organic solutions is to use Sluggo OMRI listed slug bait pellets. Sluggo works great for us in Hawaii because it remains effective after rainfall. Safe around pets and wildlife.
Garden Safe Slug & Snail Bait
Garden Safe Slug & Snail Bait: Kills Slugs & Snails
Active ingredient: Iron Phosphate 1%
Garden Safe slug bait pellets use iron phosphate to bait and kill slugs and snails in the garden. OMRI listed for organic use. Safe around pets and wildlife.
Slug Magic
Slug Magic: Makes Slugs Disappear
Active ingredient: Iron Phosphate 1%
Bonide Slug Magic pellets use 1% iron phosphate to eliminate slugs and snails organically. OMRI listed. Safe around pets and wildlife.
Slug Bait Plus: Iron Phosphate and Spinosad
If your garden is also suffering from pests such as the notorious cutworm, you may consider using spinosad to control them. Spinosad is organic and added to Sluggo Plus to control a variety of garden pests.
Spinosad
Spinosad is a naturally occurring bacterium that can be toxic to certain garden pests. Spinosad is found present in fermentation juices of the soil bacterium Saccharopolyspora spinosa. Spinosad has been certified for use in organic agriculture since 2003 by the USDA National Organic Program (NOP) and is OMRI listed.
Sluggo Plus adds spinosad to their iron phosphate slug and snail bait to target earwigs, cutworms, pill bugs, sow bugs, slugs, and snails. Other studies of spinosad’s effectiveness include thrips, leafminers, spider mites, mosquitoes, ants, and fruit flies.
How it works: Spinosad takes 1–2 days to kill pests. This organic bacterium targets the nervous system of garden pests, making them die in a day or two after consuming spinosad.
Best Organic Slug Bait with Iron Phosphate and Spinosad
Sluggo Plus
Sluggo Plus: Kills Earwigs, Cutworms, Sowbugs, Pillbugs, Slugs and Snails
Active ingredients: Iron Phosphate 0.97%, Spinosad 0.07%
Sluggo Plus with Spinosad is used to control slugs, snails, earwigs, sow bugs (roly poly), pill bugs, and cut worms too! OMRI listed for organic gardening. Rainfall-resistant. Safe around pets and wildlife.
What’s the best way to apply slug bait?
Plants are at their greatest risk of slug damage when they are young. That’s why it’s best to apply slug and snail bait before planting seedlings or cuttings.
The safest way to apply slug bait is to scatter it around the perimeter of your garden area. This tried-and-true method attracts slugs away from plants instead of attracting slugs to them.
If you must use slug bait in-between plants, consider setting up trap stations by placing slug bait pellets in lids or small containers.
Additional tips for using slug bait:
- Get rid of excess debris, dead leaves and other damp materials that may create habitat for slugs and snails.
- Repeated applications of bait pellets may be necessary if there is a large population of slugs or snails.
What are non-organic slug baits made of?
The two most commonly used active chemicals in non-organic slug bait are Ferric sodium EDTA (chelated iron phosphate) and Metaldehyde.
While Ferric sodium EDTA is recognized as safe, concerns about the high availability of iron have been raised and negative effects on earthworms.
Metaldehyde is classified as a “Restricted Use Pesticide” by the EPA and a potential contamination hazard.
Ferric sodium EDTA
The newest active ingredient used in slug and snail baits, Ferric sodium EDTA (chelated iron phosphate) is a chelated form of an iron compound made with a chemical EDTA, which makes the iron more readily available to kill slugs and snails. It’s used in not just slug bait, but also in some nutritional supplements for human consumption as a source of iron.
Ferric sodium EDTA is an active ingredient in many non-organic slug baits, regarded as a safer alternative to traditional Metaldehyde slug baits. However, ferric sodium EDTA may be harmful for humans and pets if ingested in quantity, and is toxic to soil microlife and aquatic arthropods, which is why care should be taken when using it.
How it works: Chelated iron phosphate slug bait takes about three days to kill slugs and snails. Snails and slugs that consume ferric sodium EDTA stop feeding almost immediately after ingestion, and die in about 2–3 days.
Metaldehyde
For the past 35 years, Metaldehyde was the most commonly used active ingredient in mollusk (slug and snail) bait. Metaldehyde has been widely reported on for its dangers to humans and wildlife (see Metaldehyde Toxicosis). Metaldehyde is labeled by the EPA as a “slightly toxic compound” that is often detected contaminating surface water bodies exceeding the EU statutory drinking water limit of 0.1 μg L−1 for a pesticide.
Bitrex (denatonium benzoate) is an extremely bitter-tasting substance that most mammals will not eat. In fact, denatonium benzoate is the most bitter substance known to humans. It is added to Metaldehyde slug baits as a deterrent to ingestion.
How it works: Metaldehyde slug bait takes less than a day to kill slugs and snails. Metaldehyde baits kill slugs and snails the fastest of all slug baits—often within 12 hours of application. Keep away from mammals that may feed on it, and water flow areas.
More information about slug bait
- The EPA and independent tests have shown iron phosphate slug baits as basically harmless to mammals, birds, fish, and worms when used as directed.
- Both organic iron phosphate and even non-organic metaldehyde slug baits have shown to not affect earth worms. However, Ferric sodium EDTA has been shown as being toxic to earthworms and should not come into contact with garden soil.
- When using slug baits follow all of the manufacturer’s instructions and warnings on the label. Don’t let slug and snail baits contaminate the edible (or smokeable) parts of plants.
Best Organic Slug Bait Shortlist
| Product | Controls | Link | |
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Sluggo Slug & Snail Bait | Kills slugs and snails plus insect pests | PRICE ► |
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Sluggo Plus | Kills slugs and snails | PRICE ► |
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Garden Safe Slug & Snail Bait | Kills slugs and snails | PRICE ► |
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Slug Magic Slug Bait | Kills slugs and snails | PRICE ► |
