Controlling Pests
As vegetable growers we have to be constantly on guard against predators who would like to get in on our harvest.
They’re just trying to make a living! my partner Mike says, which is a sentiment I share but don’t necessarily agree with when I see the damage that a few slugs or birds can do to my plants! So, how to protect our vegetables without harming the wildlife that abounds in our gardens? Read on to find out….
Slugs and snails
Slugs and snails… what is the point of them you may ask? You might reasonably think they’re only put on this planet to ruin your seedlings but they actually do a lot more good for our vegetable plots than we realise:
- they eat dead and rotting organic matter then return it to the soil
- they help to break down the contents of your compost heap (so put any slugs and snails you find in there to help with the composting process)
- they are food for all kinds of wildlife such as hedgehogs, birds, slow worms and frogs
Nevertheless, despite these advantages they do often seem hellbent on eating your small, tender plants and can decimate a row of salad leaves in a night. Once you’ve been found by your local slug and snail community it’s a battle of wills to see if you can outwit your new mollusc friends. I read once that slugs have 27,000 teeth and are able to put them to excellent use on juicy seedlings like courgettes or runner beans. In fact there’s not much they don’t like to eat although they only seem to go for onions, leeks etc when they’re really desperate!
I’ve tried various methods over the years to rid gardens of slugs and snails, some of which have been successful and others a complete waste of time. Here’s my assessment of what works well and what doesn’t:
Sheep’s wool pellets: these work as a barrier to stop slugs and snails getting close to your precious plants. You sprinkle them in a circle around said plants then water them. They swell up to become a coarse, woolly mat that slugs and snails find irritating to move across. The only disadvantage is that they’re quite expensive so I’ve had to use them sparingly. Check out costs here: https://www.dobies.co.uk/garden-equipment/pest-control/all/slug-gone-pellets_mh3879
Sheep’s fleece: this works like the pellets mentioned above but is free if you can get some from a local friendly farmer! My allotment neighbour offered me some fleece last year and I ended up with a binbag full. I take a handful out and fluff it up then put it around the plant I want to protect.
Nematodes: these are microscopic organisms that you water into your soil and then leave to burrow into slug and snail eggs and kill them. For them to work effectively you need to do this in spring before the eggs hatch and repeat the process every 6 weeks throughout the summer. They’re not very cheap but I’ve had some success with using them and think the snail/slug population has decreased in the summers I’ve used them. You can find out more here: https://www.nematodesdirect.co.uk/13-nemaslug-programmes
Slug pellets: I’ve had variable results with these but think it’s always worth having a container in the shed as they’re useful for sprinkling around tiny seedlings that you can’t protect with barrier methods. Previously, slug pellets used to be harmful to wildlife but these have been banned and now only those containing harmless ferrous phosphate are available to buy. That’s good news for wildlife but not necessarily for the gardener as I haven’t found them to be particularly good at protecting plants. I think they work by attracting the slugs and snails to them so they eat the pellets rather than your produce. I find pellets put out in the evening have all disappeared by the morning and plants have largely remained intact so on balance they seem to work.
Beer traps: I first started using these last year in my herb garden and was both impressed and horrified by the results. The morning saw each submerged Tupperware tray full of bloated slug corpses – they had literally been attracted to the beer from 3 counties away! So in my opinion they work well but you then have to dispose of the bodies which isn’t so pleasant….
Slug collars: another barrier method that works by encircling the plant and stopping slugs and snails from attacking young seedlings. The collar has a lip around the top that prevents our slimy friends from climbing over. One or two acrobatic ones have managed to succeed in their endeavours but these generally offer good protection from night time assaults. Check them out here: https://www.greengardener.co.uk/product/slug-collars-hosta-halos/
Coffee grounds: having read about how effective these were I relieved my coffee-loving friends of their old grounds and set to work. I may not have been using enough of them but they didn’t appear to protect my plants at all.
Egg shells: these might work but you need to eat a huge number of eggs to be able to apply them in sufficient quantities. Maybe beg egg shells from your local café and then get crushing!
Human hair: I worked with someone who said her husband collected any of her long hair he found and wrapped it around their vegetable plants in order to keep the slugs away. She claimed it worked but I don’t have long enough hair to try it myself so can’t vouch for this method.
Old jumpers: this was another tip from a fellow gardener and sounded plausible: in theory they should work like the sheep’s wool pellets i.e. a rough barrier that slugs and snails don’t like travelling across. I cut up old woollens and also tried knitting wide strips to protect rows of brassicas but they had a limited if not negligible effect on slug invasions and I’m therefore not convinced they work.
Rats, mice and birds
I had an ongoing battle with a rat this summer over my strawberries. And I’m sorry to say the rat won as he/she was up earlier than me in the morning and got the nicest fruit long before I was awake. Netting is probably the most effective way of stopping small rodents and birds from eating your fruit and veg. I bought netting in 8m lengths which can then be cut in order to cover smaller areas or left intact and draped over plants for protection using hoops or bamboo poles to create a structural framework. This link is useful: https://homehardwaredirect.co.uk/productinfo?ProductID=19788
Insects
Ideally we want to encourage a wide range of insects in our vegetable plots because we know how vital they are to soil health and pollination. However, there are some that should be distracted or kept away from our growing plants and here are tips on how to do it:
Companion planting: this can be a good way of controlling a variety of unwanted insects on your plants such as blackfly. This is a method whereby you put different plants together e.g. runner beans and marigolds and the blackfly find the marigolds far more tempting than your runner beans. Companion planting works in different ways:
- plants can be sacrificial in that the insects feast on them rather than your precious vegetables
- plants can be highly aromatic and attract insects or odorous and repel them e.g. leeks planted next to carrots, thus putting off carrot flies
This link gives you some great suggestions about what you can plant with what: https://www.gardenersworld.com/plants/companion-planting-combinations/
Netting: brassicas are particularly susceptible to cabbage fly so it’s important to protect them with the correct type of netting which has a very small mesh. Here’s a link to the perfect covering for your cabbages, kale and purple sprouting: https://www.kingsseeds.com/Products/Sundries/Crop-Protection/-Cabbage-Carrot-Fly-Netting-Size-2m-x-10m
