The Slug Year
A month by month guide for dealing with slugs.
In order to give your plants, flowers, and vegetables the best chances of survival against slug infestations, home gardeners should engage in a year round slug management programme.
It’s probably not the best weather to be doing much in the garden, but on the occasional dry day there’s always something that can benefit from a little attention. Rake over the soil and remove any remaining fallen leaves so birds can eat any slug eggs that have been exposed.
If it’s too wet to get onto the garden you could still peer beneath old stones or logs and remove any sheltering slugs and hibernating snails you may find.
Slugs aside, January is an excellent month for lounging by the fireside in your favourite armchair; making plans for all the things you’ll be doing in your garden over the coming months.
Spring is one of the slug’s most prolific egg laying periods, and they hatch in a matter of weeks when temperatures are consistently above 5°C. So you can make a major reduction to the slug population in your garden by eliminating as many as you can before they start to breed, giving yourself a head start in your war against those ghastly gastropods this year.
Every slug left to roam the garden will produce up to 200 offspring throughout the year, and in addition, the offspring will also produce young.
Continue to rake over your garden to remove leaves and plant debris, exposing more slugs and their eggs to hungry predators.
Days are beginning to warm up and slugs are starting to become active again. Digging over your garden now that slugs are closer to the surface will expose them to hungry birds, and their eggs to the elements before they have chance to hatch into a new season of munching molluscs!
Rotovating larger areas where possible is even more effective at eliminating both slugs and eggs. Aim to produce a fine tilth, thus reducing crack refuges. This produces a surface that’s less attractive to slugs but more favourable to young seedlings.
Continue checking beneath all the favourite hiding places for slugs, snails, and their eggs.
With April showers and warmer temperatures, a slug population explosion seems to descend upon the garden. Any surviving eggs are now hatching into miniature slugs that start feeding immediately, and despite their size, these tiny slugs have voracious appetites. It may seem early, but taking measures at this stage means less slugs develop into the monster munchers that wreak so much havoc during the coming months.
If these warmer spring days tempt you to put out summer bedding and plant up containers early, please be extra vigilant because slugs love tender young plants.
A mild April is often followed a colder spell later in May, and some late spring frost protection may also be required.
The garden is flourishing and slugs are out in force, with newly hatched sluglets especially ravenous. Be sure to take steps to control them before they have the chance to ruin all your hard work. Adult slugs can eat 40 times their weight daily, and can completely devour new seedlings and bedding plants overnight.
Use the various protection methods found on this site to keep your new plants safe at this critical stage of development. Once established, most can then withstand a little nibbling.
Many slugs naturally feed on decaying vegetation but at this time of year their staple diet isn’t so readily available. That’s when they turn to the tender new growth that’s so abundant in the garden.
Days are getting hotter and drier, and more inhospitable to the slug which must stay cool and moist to survive. So now the manic spring planting season is over, it’s time to turn your attention to the kind of places where slugs love to hide during these hot summer days.
The sudden burst of lush new growth provides ample places for slugs to take refuge, so keeping this trimmed to a minimum not only helps show off the explosion of colourful summer bedding, it also robs the slug of some of its daytime haunts. Keep the lower leaves of larger annuals pruned because slugs love to shelter there too.
Keep your lawn edges trimmed. This not only adds that finishing touch to a freshly mown lawn, it removes another favourite slug refuge.
It’s from places like these that slugs emerge in droves to launch their night time attack on your plants. Go on a nocturnal slug hunt and see how many of the little blighters you can collect and dispose of. It’s a surprisingly effective form of slug control.
Bedding and container plants are now more hardy and can probably withstand a little slug nibbling, but there’s no room for complacency. Now’s the time when the slug turns its attention to your tender young vegetables – lettuce being a particular favourite. It also loves juicy young fruits like tomatoes and strawberries just as much as you do!
At this time of year some gardeners drench their gardens with a hose pipe, but the wetness just encourages slugs. In fact, plants grow stronger when water is scarce because it encourages deeper root growth in order to find moisture deep below the surface.
However, some watering – particularly containers – is necessary, and this provides a dilemma. Traditionally, gardeners have watered of an evening to prevent the hot sun from drying the ground before the plants take up the water. But night time is ‘slug time’ and the wet conditions harbour them all the more.
So early morning watering is preferred. Unfortunately that does mean ‘early’ or the summer sun will immediately dry the ground before your plants get a drink.
Mid summer, and the garden is at its peak. To allow you to sit back and admire it at its best, keep things tidy – long grass trimmed, weeds weeded and herbaceous plants well pruned. The slug will hate you for it.
To mulch or not to mulch? Another dilemma! A good mulch of compost enriches the soil and traps in moisture, but do you remember what slugs love? Decaying vegetation and moist conditions. So a mulch of something drier like bark is more slug-unfriendly.
Another useful trick during the hot summer days is to learn the sort of places where slugs are hiding – beneath old bricks and boards, among flower pots and seed trays, for example. Check out these places and dispose of any slugs you find. You could even purposely create such places so you know exactly where slugs can be found.
Maintain the evening slug patrol, especially if it’s been raining.
It’s beginning to get cooler and damper, and slugs are starting to lay their autumn batch of eggs. Slugs lay eggs nearly all year round, but most prolifically in late summer and early autumn.
Keep a look out for the clusters of 20-100 tiny white spheres under boards, stones, among flower pots, or in cracks in the soil – in fact anywhere cool dark and moist. Eliminate as many of these places as you can from your garden. Exposing any eggs to predators now means fewer slugs next season.
As the summer bedding begins to die, remove it to the compost heap. If left it provides both food and shelter for slugs. This removal of plants past their best has the added benefit of showing off those still flowering.
Autumn leaves are starting to fall, providing new hiding places for slugs. Keeping them raked up removes another refuge, as well as making the garden look a whole lot better too. A carpet of fallen leaves won’t benefit the lawn, but well rotted leaf mould works wonders for soil improvement. Collected leaves can be stored in bags or in a heap separate from the main compost heap, because they decompose much more slowly than other vegetation. I use old potting compost bags.
It’s still warm enough for slugs to be active and egg laying, so remain vigilant. Remember, every egg destroyed now is one slug less next year.
Keep on top of clearing away dead and dying annuals and removing any dead leaves from perennials.
It’s easy to neglect the garden at this time of year. It’s over for another season and we tend not to care that slugs are munching on the last remnants of decaying vegetation. But it’s storing up trouble for next year.
When the weather is favourable, take a last good look around. A little time spent grooming the garden will certainly improve its overall appearance for the rest of the autumn and winter.
If the ground isn’t too wet, dig it over. This exposes both eggs and sheltering slugs to the elements and to other birds and animals. A secondary benefit is that it gives the winter frosts chance to break down the soil still further, ready for next Spring.
If you’ve taken care of all the aforementioned tasks, any weary slugs have probably given up the fight and moved on to a less slug-unfriendly garden, leaving you to look forward to a springtime of reduced slug aggravation.
Give yourself a pat on the back, take a month off, and make preparations for an enjoyable Christmas season.
OK, so now you know what to do in May to banish slugs, but what else needs to be done in the garden this month?
The Gardener’s Year
Dad always said to me, “Gardening is tied to the seasons, and being a successful gardener is all about planning ahead.”
You need to know what you should be doing, when, and why, so what needs doing in May?
What do you want to do now
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Britain is home to around 30 species of slug