Slowing down slugs
This project is now CLOSED.
Preventing slugs and snails from nibbling on veg is one of gardening’s most familiar challenges. With many of us looking to reduce the use of chemical controls, home remedies and other methods are becoming more popular again (and many never left) – but how well do they actually work?
In 2019, the Buzz Club investigated!
The Royal Horticultural Society recently looked at what might work for reducing grazing damage on leafy crops, although none of the remedies they tested performed strongly. Because many of our members focus on growing plants that are fairly robust once estabished / leaf damage is less of a concern (such as peas, beans, sunflower etc), we looked at the remedies that might have been able to slow the slugs until the plants get established.
No effect was seen (see below for details) in the amount of damage done to the plants under either a remedy, or a control treatment (control = none). The main effect that did reduce the damange done to plants was physically moving them out of the way of slugs, such as up on a table. This was the same effect shown in the RHS study.
More details on our results can be found in Issue 12 of our newsletter, archived here.
New plants. Exciting, but delicious. Particularly annoying to lose them at this stage if you do not have a lot of space for seedlings - like Linda's grow bench here.
Established plants. Tougher overall, certainly less likely to be chewed through at the base.
So what does this mean?
There’s no need to spend money on rolls of copper tape, for one thing! The intervention that worked best for protecting young plants was getting them out of harm’s way, where it was difficult for menacing molluscs to get to. We hypothesise that on e.g. a table with narrow legs (only 4 small points of contact with the ground) might be better than up on an old bin that touches the floor all the way around (although we didn’t test for this). If you have particularly voracious slugs, try dedicating a table to your beans and squashes for a few more weeks before planting out.
Some participants’ anecdotal reports suggest that although sheeps’ wool (and possibly grit) don’t seem to do much to deter slugs, it does seem to be a good mulch, keeping plants from drying out.