Common Garden Pests & How to Keep Them Out Your Garden
There’s nothing quite so disheartening to a gardener than discovering all your hard work has been eaten or otherwise destroyed by marauding garden looters.
Since the beginning of time we’ve been fighting to keep our crops healthy and ensure we have enough to feed ourselves. Luckily these days we don’t need to worry about starvation, but it’s still miserable to find a damaged plant that you’ve spent a lot of time and money on.
Garden pests are creatures that eat your plants. They range from rabbits to slugs, snails and insects. Pests are different from disease. Diseases include fungus, black spot, rust or blight – but that’s another topic!
Let’s take a look at what garden invaders are likely this year and how you can deal with them...
Cat and Foxes
Cats and foxes can be a nuisance. Cats see your freshly dug border or pea shingle as a huge litter tray, dig up seedlings and disturb plants. Foxes dig up the soil looking for earth worms, go through the bins and make a frankly appalling smell when they mark their territory.
How To Stop Cats and Foxes Coming in Your Garden
Remember it is against the law to hurt or poison animals. Cat deterrents work but need replacing especially after rain. Some people swear by lion poo which you can buy online. If cats are a persistent problem use ground cover plants to protect bare earth and net your seedling areas – or you could get a dog!
There are several good fox deterrents, but they're usually looking for food, so don’t leave out scraps, get a tight lid for your bin and compost heap. Use chicken wire to net any holes in your fence. If you have outside pets such as rabbits, ensure they are locked away before sunset in a sturdy hutch.
Slugs and snails
Even the staunchest townie can identify a snail or a slug. They come in all colours but have only one thing on their minds – eating your plants. Slugs and snails will eat anything green. They love lettuce, cabbage, clematis, hostas, even potato tubers. Nothing is safe, particularly when it’s damp.
How to get rid of slugs and snails from your garden
If you can’t spot a snail but see silvery trails across your patio, fence or soil, you can be sure you have them. They eat ragged holes in leaves, and some species even tunnel into the earth for roots. They lay eggs on your tender greenery so minute versions can continue the rampage a week later. It bringing me out in a sweat just thinking about them!
Many people choose to use pellets. They work well and are easy to use. Unfortunately they don’t do other creatures much good. If you must, use them sparingly and pick up dead slugs and snails the morning after so birds and hedgehogs don’t eat them.
There are lots of ways to contain slugs and snails that don’t require chemicals – here are a few of the most effective:
1) Pick up the snails and move them elsewhere. Use a field not your neighbour’s garden as they will just head back!
2) Nematodes sound terrifying but are simply natural predators. You can buy them online. Slug and snail nematodes are tiny eelworms that are watered into your soil. They infect snails and slugs with bacteria.
3) You could also buy a trap from your garden centre or even make one yourself if you are inclined. Simply sink jars of watered down beer into the earth around your prized plants. The snails and slugs fall in. It’s not much fun emptying these, but empty them you must! Butter tubs, squash bottles and other recycled bits work well too.
4) Or you can make the environment uncomfortable for them. Placing copper tape around container rims gives the wet-footed pests a quick electric shock. Gravel, eggshells or stones make a rough barrier. Slugs and snails like wet smooth ground, they don’t like a prickly surface. Surround your seedlings moat-like with a gravel barrier.
5) Rake over your soil as often as possible to disturb their hiding places too. Snails and slugs like dark wet homes so they don’t dry out. Check your hostas, ferns and any other leafy plants that could provide a comfy home.
6) Slugs and snails are tasty treats for certain creatures, so if you’re not using pellets encourage hedgehogs, birds, frogs and toads into your garden. They will do the hard work for you.
We like to attract birds to our gardens, but often all the feathers we spot are grey. They eat everything and mess all over the lawn, not mention your car.
How to get rid of pigeons from your garden
The best way to keep pigeons out of the garden is to keep all bird food in feeders or on a table that they can’t get into. Try netting any green vegetables such as cabbage as they will strip leaves back to nothing in a few hours, especially if we have cold weather.
Aphids are tiny sap-sucking vampires that feed on vegetables, fruit, and flowers. Aphids usually feed on the leaves, foliage and stems stunting plant growth and leaving a sticky substance behind. This is called honeydew but it’s a far cry from the attractive name. There are over 500 types of aphid in the UK – get me a drink! However, you can control them whether they are greenfly, blackfly, mottled, fluffy or woolly versions.
You’ll spot aphids clustered on your plants. If you don’t spot moving aphids you might find curled over leaves. If you open these you’ll find aphids sheltered inside.
Sometimes ants farm aphids so if you notice ants heading in one direction they may lead you to the aphid farm. Sooty fluff and stunted growth all indicates an aphid infection, particularly on young plant tips and beneath new tender leaves where the sap is sweetest.
How to get rid of Aphids
You can spray them with a bug killer. This does a good job and they are unlikely to return. However, chemicals are not the only way to banish aphids. If you are not squeamish, pop on some washing up gloves and run your fingers across the aphids to squash and remove them.
You can also make up your own spray. Soak the peel of a lemon or orange overnight in hot water, and spray it directly on the aphids. They also dislike soapy water. You’ll need to do this a few times for results, but it does work if you have patience.
If you spot a ladybird pop her on the aphids. Ladybirds are the natural predators of aphids along with lacewings and hoverfly larvae. Leave spider webs intact too as spiders eat the aphids that land in their webs.
Companion planting is an underestimated ploy for pest control. The Tudors used it in their kitchen gardens well before pesticides were invented. It’s all about using plants that pests don’t like. French marigolds for example clear aphids and whitefly from tomatoes. Mint and garlic are also stinky enough to deter flying pests.
Aphids are less likely to damage a healthy plant so make sure yours are in tip top shape and able to withstand some aphid action.
If you grow green veggies you will be familiar with the white butterflies that lay eggs on the underside of the leaves. These develop into an army of very hungry caterpillars. It’s cute in the children’s book, not so much in the garden. The eggs are usually small, orange and laid in perfect lines. The caterpillars are black and yellow and VERY hairy! The small cabbage white caterpillar is small and green with soft hairs. You’ll know you have them when holes appear in leaves. You may also find, I’m sorry to say, caterpillar poo.
Scraping off the eggs works very well, use washing up liquid and gloves to get traction because they are sticky and tiny. You can also net your greenery to prevent butterflies getting there in the first place.
Of course you may choose to spray. Be careful and follow the instructions. It is better not to spray vegetables that you are going to eat, but sometimes infestations are so bad there’s little choice.
Box tree caterpillar
This is a fairly new pest that has seen a sudden rise in numbers. If you have any box (buxus) in your garden, beware of the box tree moth. Look for caterpillars that are about 4cm in length with black stripes. They can be found beneath box leaves under fine white webbing. They grow from tiny yellow eggs that are flat and overlap like scales. The moth itself is white-winged with a brown border.
Your box will suffer die back and damaged foliage from this unlikely looking pest.
How to get rid of box tree caterpillar
If you want to treat box with chemicals try an insecticide as most will destroy the eggs, but if you don’t like chemicals simply remove caterpillars when you spot them. If you have a bird table give your robins a treat. They love caterpillars and they make great soft food for hatchlings. Another effective non-chemical control is a pheromone trap that lures male moths in.
Ok, this is a trick inclusion. Woodlice aren’t pests but you may find many of them in your garden. They might have a nibble on young soft shoots, but prefer to eat decaying materials. If you want to be rid of woodlice clear away rubbish and turn over your earth regularly.
Another of my sworn enemies, these larvae burrow into shrub stems. You’ll identify them when you move close and they rear up onto their tails in an ‘S’ shape. As with most flying insects it’s the larvae that do the damage. Sawfly lay their eggs on plants such as roses, gooseberry, trees, and flowering shrubs with the result of defoliation. The larvae are usually green with black spots.
How to get rid of sawfly
You can use a chemical spray but the best way to deal with sawfly is to remove them by hand. Serious infestations can kill a plant.
Roses and shrubs are targeted by leaf-cutter bees that do no more damage than their name suggests. You’ll spot a circular cutting in a leaf. This is taken to build a nest. It can look unsightly but doesn’t damage the plant. Given the benefits we gain from pollinating insects I think we can forgive these bees a few holes.
Chances are you’ve spotted this quick and hungry pest but don’t know the name. Vine weevils are beetles that eat a wide range of plants, but particularly those in pots. They are very common. Often grubs have done the damage before your plants even flower. Grubs live in the roots eating their way to maturity during the winter. Strawberries and rhododendron are favourites.
You’ll spot a vine weevil when you notice notches in your plant leaves. They are irregularly shaped and often blamed upon slugs. Look closer and you might spot a beetle that’s almost black but has splodges of dull yellow on its wing cases. They usually measure 10mm long and have lengthy antennae. The grubs are white with a brown head.
How to get rid of Vine Weevil
What can I say? Squash them if you value your plants.
Look in the foliage and under pots for vine weevils. The RHS has a great recommendation - in the evening take an umbrella outside, hold it upside down and shake your plant. The weevils fall out into the brolly. Natural predators for vine weevils are frogs, toads, hedgehogs, birds and other beetles, so it’s worth encouraging them.
There’s also a nematode available for vine weevil that’s worth a go if you just can’t shift them. Chemicals can’t be used in open ground, but in pots you can use a compost drench to kill the grubs.
Ants don’t eat your plants but many gardens have them. Does anyone remember hiding indoors when a flying ant nest hatched in summer?
Ants are useful because they can lead you to aphids. They farm aphids because they love the sticky honeydew. Conversely, ants won’t cross anything sticky, so Vaseline around a shrub stem works wonders. You should also keep the ground damp as they prefer dry conditions. Don’t worry about ants too much though, not when there are slugs and aphids more worthy of your attention.
Being kind to the environment
It’s worth remembering that as annoying as these animals and insects are, they are only trying to survive. It’s not personal! Pests are part of the food chain, wiping them out entirely disrupts nature’s balance and can’t be a good thing.
Often the best way to tackle pests is to detect them early. Don’t let a full on infestation happen, as this can be pretty tricky to deal with without resorting to chemical sprays.
If you choose to use chemical sprays - use them wisely. Don’t spray near children or animals, wear gloves and don’t stand downwind. It’s best to spray any chemicals in the evening, preferably by torchlight so that bees and other helpful pollinators are not directly sprayed. Shake the plants first to dislodge spiders and ladybirds and always follow instructions on the label.
You should only need to use a chemical control once or twice over the summer. Remember they are indiscriminate and kill most things they touch.
I wish you the very best of luck in your battle with garden pests this year! Give those natural non-chemical methods a go before dusting off the spray. They do work with persistence and you’ll get those feel good vibes from helping our native wildlife.