If you don’t protect new seedlings, seed-sowing can be a hit or miss business. Slugs and snails are the biggest problem for young seedlings, but you can protect tender plants from them using copper tape and bottle cloches. These can be re-used, and will work for as long as they are needed – unlike slug pellets! You can make your own cloches easily enough by cutting rings out of old plastic bottles, and wrapping bright copper tape around the upper edge. You can even use a line of these to protect a row of delicate seedlings like carrots, and if the plastic is tall enough they will keep larger pests like mice out too.
Unless you take steps to protect young plants from slugs and snails, seed sowing can degenerate into keeping your fingers crossed and hoping that a wandering predator doesn’t encounter your plants for several weeks. If one does, you can be sure it will return the following evening – and so on, until you have a serious problem. At the beginning of the gardening season, whatever you sow will quickly become the tastiest thing around, and any predators in the vicinity are sure to gather for a meal. Then you have to re-sow, and re-sow, and maybe re-sow again, until you eventually get a viable crop – but you’ll have lost weeks of valuable growing time.
Keeping slugs and snails off your seedlings
In fact, protecting your plants is easy. Cut the tops and bottoms off plastic bottles to make a tube. If slugs are the particular problem, wrap a piece of sticky-backed copper tape around the tube near one end. Push the other end into the ground around the seedling, and you have a slug-proof barrier. Contact between slug and snail slime and bright (untarnished) copper generates an electrical current which stops them in their tracks, so they never get to eat your seedlings. And, if the cloche is tall enough, mice can’t get in either.
Unfortunately, some slugs live beneath the surface of the earth and come up at night – and if one comes up inside the cloche it must be a bit like tunnelling into a 4-star restaurant. So, a slug patrol or two with a torch in the evening is still a good idea until you’re sure that ‘residents’ such as these have been collected and removed.
Sometimes it’s tempting to leave the cloche in place until the seedling is getting quite large – but be careful. If you leave it in place too long, you’ll damage the plant when you try to remove it. To avoid this, you can cut through the plastic ring when you’re making the bottle cloche, so that it can be opened into a C-shape. This means that it can be lifted away more easily. It takes a bit more care to put these in place, as you have to make sure that there are no gaps that slugs and snails can get through, but another benefit of ‘slit’ cloches is that you can use two or even three to create a ‘super cloche’ that can protect much larger seedlings that might still be a tempting meal – squashes, cucumbers and courgettes, for example.
Carrots and parsnips
Carrots and parsnips spend a long time as small seedlings, and do much better when they are sown directly into the soil bed rather than into modules. This makes them really vulnerable to slugs and snails. Once they’re bigger it doesn’t matter so much, but if anything takes so much as a single bite out of a very new seedling, it’s over. Bottle cloches, with or without a copper strip, are an excellent way of protecting tiny seedlings such as these.
Plant the seeds directly into the beds, in rows. Then push the cloches down, one after another, along the rows with as little space between them as possible. Almost all the seedlings will then come up inside a cloche. Once they’re big enough to keep going on their own – or, if you need to thin the crop – lift the cloches carefully.
Peas and beans
Peas and all types of bean are substantial enough to be less at risk from slugs and snails, but this makes them popular with birds and with rodents, especially mice. A cloche placed around each one allows them to grow undamaged until the remains of the seeds just aren’t worth it any more. As peas and runners will climb quickly, it’s best to use slit cloches so that they can be removed from the plant without disturbing the stems.
After the crop
Once you’re finished with your bottle cloches, store them in a bag until they’re needed the following year. It’s a good idea to wash them at the start of the season, as they tend to get muddy and this will restrict the amount of light getting to your seedlings. Copper tape is only effective against slugs and snails when it is bright (untarnished), so it doesn’t last forever. When it goes dull it will have to be replaced, although giving it a gentle rub with glasspaper (an ultra-fine grade of sandpaper) is sometimes enough. If you’re gardening in a polytunnel or greenhouse, consider putting a strip of copper tape right around the doorframe – or at least, across the threshold and halfway up the sides. This will prevent new slugs and snails coming in from outside.