Mild weather means we enjoy our gardens more, but slugs and snails – the dreaded gastropods, tend to enjoy our gardens more, too. Just like us, warmer weather and luscious plant growth are very inviting to these slimy creatures, bringing them out to feast on our much-loved young plants. While it’s tempting to reach for slug and snail pellets, there are good reasons to go for an organic approach.
The slimy crew actually play an important role in a healthy and biodiverse ecosystem. They are a succulent morsel for many creatures, from toads to hedgehogs and even glowworm larvae, which are specially adapted to eating these creatures. On biting their victim, glowworm larvae deliver a fatal dose of poison, which paralyses the poor creature and begins to turn it into a soup that the larvae can easily slurp down. Not my idea of a yummy supper, but each to their own.
Glowworms are an enigmatic and now fairly rare part of British wildlife. A study published in 2020 showed that, over the course of 18 years, their numbers had dropped by 75%. This decline has been caused by the usual culprits: habitat loss, changing weather patterns and the widespread use of pesticides and herbicides. Currently, gardens in England cover more land than our national nature reserves combined – so they can provide an invaluable network of organic and, therefore, safe environments for wildlife, such as the glowworm.
If you’d like to encourage garden glowworms, they enjoy meadows, grassland, hedgerows and an ample supply of slugs and snails. It is worth noting you will also need to reduce light pollution, as this is a driver for their decline.
As well as providing a food source to so many, slugs and snails also play a big role in cycling “waste” in the garden. Only nine out of the 44 slug species in the UK like to eat living plants. The rest are detritivores, preferring to suck up decaying organic matter – meaning they are important recyclers. Slugs and snails are so valuable, in fact, that the Royal Horticultural Society no longer classifies them as pests and the toxic pesticide, metaldehyde, once used in farms and gardens to kill them, has now been banned.
If, like me, you are convinced of their important role in an ecosystem, but still don’t want your plants obliterated, there are organic solutions. Trials have shown that wool, eggshells, copper tape, sharp grit and pine bark mulches don’t work long term. What does work is cultivating a healthy garden ecosystem that can manage the slug population at a reasonable level. This can be done by growing organic, diverse planting with many natives, creating ample habitat for predators and maintaining a healthy soil that can support healthy plants.
We can also employ predators, such as nematodes, ducks or chickens, in our gardens. We can grow extra plants to fill any gaps and keeping plants healthy also reduces chances of gastropod attack, while watering in the mornings means that plants are less wet and inviting in the nighttime when the slimy folk come out. But what I find most effective is simply covering young plants so they can’t be got at. I use cloches, plastic bottles or glass jars to act as physical barriers, until I think the plant is vigorous enough to withstand some nibbling. I tend to put them on in the evening and take them off each morning (unless it is an exceptionally wet and grey day). Once the (hopefully) hot dry summer comes along, slugs and snails will be less of a problem in any case. Nursing young plants through spring is the real challenge.
The chamomile, sown in early spring, is one such plant that I will protect. I keep the germinated seedlings in a tray, allowing their roots to mat together into a bit of a brick. Then, once they have grown to about 10cm tall, I break the brick into clumps and plant them in empty pockets of the garden or along the edges of the vegetable beds. They want full sun and minimal competition. Once they have settled into their new home and put on some good growth, the protective jars come off for good. Then the wait is on for summer flowers.
The peas which were sown directly in the ground in early spring, have risen. I sowed them densely. Some of the crowd have succumbed to the slimy ones, but many survive. They are grown in two thick rows, so it’s not possible to protect them all with jars. I can only hope and pray that some of them make it through.
It’s time to give the peas some support. I find in my small garden that pea netting is more efficient than hazel pea sticks, which look pretty, but take up more space. I create a frame with bamboo canes. Two 1.5m canes lean into each another at both ends of 1.5m-long row, tied at the top. One final cane runs between the pairs, up high and parallel with the ground. I then hang the pea netting over the structure, like a tent made from net. Eventually, this will be a tasty green wall.
The young tomatoes that were also sown this month are starting to look confident. I won’t plant them out in the greenhouse until the start of May and we can do that together in my next column. In the meantime, I feed the tomatoes an organic, homemade plant feed. The recipe for which is in this month’s garden jobs.
Three jobs to do in April
Make your own plant ‘soup’, tackle perennials and stay peat-free
Homemade organic plant feed
Ingredients: as many nettles and/or comfrey leaves as you can manage; and plenty of water (ideally rainwater, if you have collected it in a water butt). Method: Chop the leaves and pop them in a bucket with a lid. Submerge with water and weigh down with a brick. Leave the brew somewhere with its lid on to decompose (be warned, it is a stinky process). The extraction can be left for anything from three days to six weeks or more. Stir daily. I find the warmer the weather, the faster the process. Once it is brewed, strain off the leaves and dump them on the compost heap. Use the liquid as a foliar feed or water it into the plants’ root zone. Dilute 10 parts water to one part feed; you can make it stronger or weaker depending on how your plants respond.
Chop back perennial growth
As temperatures rise, insects hibernating in the undergrowth will be stirring and getting ready to leave their winter homes. Clear away any brittle stems left standing from last year. They can be turned into a dead hedge, chopped up and put on the compost heap or chipped and used to mulch paths. I mulch my veg bed paths with perennial growth each spring.
Peat-free April
Peat is organic matter that is partly decomposed in wetlands. It is formed over thousands of years. Peat bogs are significant carbon sinks, and those in the UK store more carbon than forests in Britain, France and Germany combined. They are also a significant habitat and protect against flooding, acting as big sponges. Peat is also used in horticulture as a growing medium. When it is dug up, carbon is released and the important landscape is destroyed. This year, the UK government banned the sale of bagged peat for amateur horticultural use, but it is still used for growing plants to sell. Support peat-free nurseries and suppliers. You can find a list on the Peat Free April website (peatfree.org.uk) and support the campaign to keep peat in the ground.