As summer advances many gardeners begin to notice more and more slug damage. Holes begin to appear in hosta and lettuce leaves, dahlias and other plants begin to look tattered, and slugs may even be found in produce as it is harvested from the garden. There are measures that can be taken to minimize slug damage and keep these troublesome garden pests under control.
One of the simplest methods is to pick the slugs by hand. I often get up early in the morning while the grass is still wet, and with a can of soapy water in hand as a depository for the slugs, I gather them up. At this time of day they will be stretched out as they crawl over the grass heading back to their daytime hiding places and are easy to see. If you are squeamish about picking them up with your bare hands, wear thin garden gloves or scoop them up with a hand trowel.
After performing this task a few times, you soon realize their favourite haunts and do not need to scour the entire garden. I also carry a piece of bamboo stick with which to lift up foliage such as beans and carrots in the vegetable garden and lady’s mantle and cranesbill in the perennial borders. There are always a few slugs under these plants. I also place old boards in the vegetable garden on which to walk during the summer to keep shoes clean and to prevent compaction of the soil. On my morning searches I flip over these boards and pick the slugs which have collected under them – often attaching themselves upside down to the boards.
I do try to protect some of my favourite plants and ones particularly favoured by the slugs. They love hostas, so in the spring when I groom my hosta bed I pour sharp sand around each plant. This deters the slugs because they hate anything scratchy, as their bodies will be cut by the sharp sand particles when they crawl over it. By summer’s end my hostas have only a very few slug holes in them, so this technique really works. I also use some old pieces of copper wire – old electrical wire with the coating removed – to surround other plants to protect them from slugs. Apparently the wire takes on an electrical charge when the slugs attempt to crawl over it – but whatever the reason, it seems to work!
Good maintenance also will discourage slugs from entering the garden. Try to avoid having a lot of foliage sprawled on the ground; for example, I make sure any tomato leaves that are touching the ground are removed. The fewer places slugs have to hide during the day will also discourage their presence in the garden, so anything that they can crawl under to spend the day should be removed – except for the old boards that I mentioned, which are used as “traps” to entice them to crawl under them where they will be ready for picking.
There are chemical slug baits available but they are expensive and some quite toxic to birds and pets, so I do not bother with them. By using the methods I have mentioned I keep slug damage to a minimum in the garden and I have learned to tolerate the damage that does occur. We gardeners have long since realized that we are dealing with Mother Nature and we cannot control every aspect of her domain!
– Albert Parsons writes from Minnedosa, Manitoba