Does it feel like a losing battle sometimes? Don’t worry, there are ways to control these little creatures.
I’m not a fan of using pesticides or any kind of toxic poison in the garden unless it is really necessary. Most of the time there are harmless alternatives that can do the trick.
I don’t mean I like the taste of them in garlic butter, I mean I like them as interesting little creatures. When I observe them, I love the way their little long eyes move about like small antennas.
They curiously poke the air and then quickly disappear inside their shell when sensing danger. Slugs may not be as cute, but I think of them as divorced snails, shuffling along and complaining that their partner ‘got the house’.
As much as I get angry when my plants have been attacked by them, I know they are part of nature and the eco system.
I don’t want to use slug pellets because they are poisonous to birds and other wildlife. Instead I have tried alternative organic methods to control them and most of them are home-made, from things that you can find in your kitchen or easily bought online or from garden centres.
As a gardening enthusiast with several Argentine senna shrubs in my backyard, I’ve dealt with my fair share of slug issues over the years. These slimy pests can be incredibly destructive, munching away on ornamental plants and leaving unsightly holes in leaves and flowers. If left unchecked, a serious slug infestation can even kill young shrubs.
In this article, I’ll provide a comprehensive guide on effective ways to get rid of slugs on Argentine senna shrubs, including both organic and chemical treatment methods.
Identifying Slug Damage
The first step is learning to recognize typical slug damage on your shrubs:
-
Irregular holes in leaves, flowers, stems. Slugs use a rasping mouth to chew through plant material, leaving ragged edges.
-
Slime trails on leaves and soil surface. Slug activity leaves behind shiny silvery mucous trails.
-
Wilting, yellowing of leaves. Extensive feeding damage can cause extensive foliage loss.
-
Presence of dark brown or black mollusk-like creatures up to 2″ long on the soil or shrub at night.
Thoroughly inspect the undersides of leaves and younger stems where slugs like to hide during the day. Damage tends to be worse in moist shaded parts of the garden.
Organic Slug Control Methods
For mild infestations organic methods can effectively remove slugs without resorting to chemicals
-
Hand pick slugs after dark and drop them into a container of soapy water, Crushing them can attract more slugs
-
Set out shallow pans of beer near shrubs to attract and drown slugs. They are drawn to the yeasty smell.
-
Use diatomaceous earth around the base of shrubs to cut slugs with its sharp edges as they move across treated areas. Reapply after rain or watering.
-
Attract predator beetles, frogs, birds to your yard with suitable habitats. They will naturally feed on slugs.
-
Set planks out in moist areas overnight to attract slugs, then collect and destroy them in the morning.
Chemical Slug Control
For heavy infestations, baits and chemical treatments offer quick and effective control:
-
Apply slug bait pellets containing metaldehyde or iron phosphate around affected shrubs. These are deadly to slugs but safe for pets when used as directed.
-
Spray plants with insecticides containing spinosad, which kills slugs on contact but won’t harm most beneficial insects. It provides rapid knockdown of pests.
-
Use slug traps that lure slugs in and trap/drown them in a pool of liquid. Dispose of dead slugs promptly.
-
Sprinkle diatomaceous earth (DE) around the base of plants to shred slugs. DE provides lasting protection even after rain/watering. Wear a mask when applying to avoid inhaling dust.
-
Coffee grounds sprinkled near shrubs repel slugs due to the caffeine. Refresh after rain. Avoid piling near stems to prevent rot.
Preventative Measures
Good gardening practices can help reduce slug populations and damage:
-
Remove leaf litter, boards, garden debris that provide damp hiding places.
-
Hand pick slugs after dark using a flashlight and dispose of them.
-
Encourage natural predators like birds, beetles, frogs that eat slugs.
-
Improve drainage in overly damp areas of the garden. Slugs thrive in perpetually moist spots.
-
Use drip irrigation instead of overhead watering to keep foliage dry.
-
Apply a 2-4 inch copper flashing around shrub stems. Slugs won’t cross over it.
-
Add sharp materials like crushed eggshells, diatomaceous earth around plants.
Protecting Your Argentine Senna Shrub
Left unchecked, slugs can quickly defoliate and damage ornamental shrubs like Argentine senna. Implementing a combination of organic, chemical and cultural control measures can help eliminate existing pests while deterring future infestations. When it comes to protecting my prized senna shrubs from these bothersome mollusks, I use beer traps, slug bait, and copious hand-picking to achieve slug-free plants. With vigilance and persistence, you can defend your landscape shrubs against these pesky invaders.
Crushed egg shells
This is so far the best method that has worked for me, together with the nematodes. Every time I make an omelette or use eggs, I keep the shells to dry on a container that I keep especially for this purpose. Once they are completely dry (some people dry them in the oven), you can crush them finely and store in an airtight container. I find a pestle and mortar easiest to grind them. Once I have a good quantity of crushed egg shells, I sprinkle a good layer around plants that are vulnerable to slugs and snails. In my garden, lupins are the slugs favourite, but last year they managed to grow nicely thanks to the crushed egg shells around them. Find how to prepare your egg shells and other useful tips here.
Natural Slug Control Methods
This is one of my preferred methods of slug and snail control. Nematodes are tiny organisms that basically cause the death of slugs by bacterial poisoning and are completely harmless to pets or children. They are not cheap, but they are very effective. The only problem I found is that as my garden is not small, I didn’t buy enough to cover all of it. But I would say that it’s the most effective way to control slugs. It’s not as effective on snails though, as they live over ground and the nematodes work underground.
I have tried this and it was a great success. You fill small traps with beer and sink them into the soil so that the edges are flush with the ground. The snails and slugs are attracted by the beer and fall into the trap, literally. However, you do have to have a strong stomach when emptying the traps. The sight and smell of stale beer and dead slugs is not something I will remember fondly. For that reason, I haven’t used this method again.
This is something I haven’t tried myself, but I thought it was worth mentioning as I’ve heard other people have had some success with this. All it involves is scattering used coffee grounds around any plants you want to protect and apparently the caffeine in the grounds is toxic to slugs. With the amount of coffee I drink, I doubt I’ll run out of supplies so I’ll give it a try and report back to you.
I must admit, I haven’t had much success with this one. You can buy sticky copper tape from most garden centres or even online and you stick it to the rim of plant pots that you want to protect. The copper emits an electrical charge when the slugs or snails try to cross over it to get to the plant. That’s the theory but my slugs and snails must be made of sterner stuff than others because they didn’t find this a problem. So this method gets a thumbs down from me unfortunately. If you have had any success with this, I would love to hear from you!
This works as a barrier method around plant pots. Just smear a good layer of Vaseline around the rim of the plant pot and this stops the slugs from getting to the plant. If you don’t have Vaseline to hand, Petroleum jelly or Vicks will do just as well.
A very simple way to make a trap for slugs and snails is to use half a scooped out grapefruit peel and place it face down near the plants you want to protect. Slugs like dark damp places and will find their way into the hollowed out grapefruit. Check the next day and see if there are any snails or slugs underneath. Apparently you could also use half oranges or lemons. Personally, I had all sorts of other bugs in them but found no slugs. Not sure if this has worked well for others but it’s an easy thing to try.
This is a relatively easy way to control slugs and snails but also time-consuming. Snails and slugs tend to come out in the evening, especially if it’s damp and this is a good time to go out with a container and a torch and just hand-pick your little enemies.
A very easy and beneficial way to control slugs and snails is to attract wildlife that feeds on them. Attracting birds by providing bird tables and water is a good way of controlling their numbers. If you can build a pond in your garden and attract newts and toads who love to eat them, you can control their numbers. Hedgehogs are also great animals to attract in your garden and will help keep the snail numbers down.
I don’t have any more slugs. 3 simple proven ways to get rid of slugs without chemicals
FAQ
How do I permanently get rid of slugs?
What can I spray on my plants to keep slugs away?
Can plants recover from slugs?