Any grower of plants wants to find a way around the annual onslaught of unwanted guests nibbling on things we'd rather they didn't. In our patch of the planet, one way we do it is by treating it as a “predator farm.”
We don't like the word 'pest' here at Patch of the Planet. Labelling a whole species just by a habit or two that we find frustrating feels wrong. But it's true that there are sometimes visitors to the patch that are less welcome, thanks to some of their habits.
These visitors are just living things trying to get by in the same space as you, eating the things they need to eat, as you do. They are a part of the system and usually, there are other things living in your patch that depend on them as a food source. As far as possible, we want to find a way to get the whole system in balance rather than obliterating one part of it.
If we want to grow a lot of delicate plants in our gardens one thing that may help is a change of mindset, becoming more comfortable with nibbles on leaves. But another thing that can help is attracting the animals that like to eat our unwanted guests - predators.
Let's have a look at some of the common unwanted visitors, and some of their main predators. Then, at the bottom, we suggest a few ways to make those predators feel welcome.
The unwanted guests and their predators
First up, here is a list of a few less welcome visitors, all of which have a number of predators:
The less welcome visitor | About |
 | Not all caterpillars are problems by any means, and all of them become moths and butterflies. But some do bring challenges to the gardener. Take for example, the cabbage caterpillars, which feed on many brassicas, turnip, swede, horseradish, nasturtiums and more. They can destroy whole plants in days. |
 | Most slugs and snails will eat at least some of your plants and many will eat a lot of them – often chewing through whole plants, leaf, stalk and all. As if you needed telling that… |
 | The RHS puts it well: “sap-sucking insects that can cause a lack of plant vigour, distorted growth and often excrete a sticky substance (honeydew) on foliage which allows the growth of sooty moulds. Some aphids transmit plant viruses which can be a problem on strawberries, raspberries, tomatoes, cucumbers, dahlias, tulips, sweet peas and many other plants.” |
Vine weevil:  Copyright Fryderyk | One of the most widespread, common and devastating garden visitors, it is especially destructive of plants in containers. Adult vine weevils eat leaves, and the grubs eat roots, which can ultimately be more damaging. |
Bothersome beetles:  | Many beetles, especially ground beetles, are an essential part of the predator mix. But some others are more of a challenge. The Rosemary beetle for example, whilst beautiful, eats the foliage and flowers of rosemary, lavender, sage, thyme and some other related plants. |
The top predator team
If you can attract the these seven masters of their art to your garden and make them loved enough to want to stay, you won’t be alone in your quest to limit damage.
The predator | About it |
 | One of the most diverse species on earth, these often tiny wasps don't sting people at all, but instead lay their eggs inside hosts, including spiders, aphids and caterpillars. The eggs hatch and grow inside their host, often exploiting them as "zombies" in ingenious ways, before killing them and turning into adults. Gruesome, but handy. |
 | Frogs and toads love to eat slugs and snails and will scatter across your garden in dark, moist spaces. With a good environment, they will stay and breed for many years. |
Ladybirds:  | Both adult ladybirds and ladybird larvae eat aphids on mass. Ladybirds are easily recognised but their larvae are not so well known. It's worth learning what hey look like so you can celebrate when you see them in your garden. |
Lacewing larvae:  | Beautiful, delicate flies, Lacewings are important pollinators. Their larvae however are amongst the best predators there are. They are voracious devourers of mites aphids, caterpillars and insect eggs amongst others. |
Hoverfly larvae:  | |
Ground beetles:  | These wonderful, stunning little creatures eat a huge range of prey including caterpillars, aphids, weevils, slugs and snails. Most of them hunt by night, but some are diurnal, so keep your eyes peeled. |
No garden is truly a patch of the planet without birds frequenting it. And as it happens, many of them have a taste for caterpillars, snails, slugs, aphids, weevils and beetles. Song Thrushes love snails, as do Blackbirds and Thrushes (who also love slugs), Tits love aphids and caterpillars whereas House Martins love aphids, flies and beetles. Goldcrests love all manner of insects. Starlings eat a whole range of invertebrates including snails, caterpillars and flies. |
So how to do it? Creating a Predator Farm
By creating the conditions, and planting the plants, that these predators like, you can help attract them to the garden in enough numbers, early enough, to help out. Here are some key things to do. It is a good idea to have plants and conditions all over your garden that attract these predators, especially near to where the problems tend to arise.
1. Allow a few nettles
One of the challenges of working with predators is that often their numbers don’t build up until later in the season, by which time some visitors have already done a lot of damage. A few nettles can help with this challenge. They are loved by a wide range of aphids, including one that uniquely eats the nettle plant. And they come up very early in the season and so become a host for aphids early on.
Allowing them to grow creates an early food source for several of your predators, which can build up their numbers earlier than they might otherwise. Ladybirds will lay their eggs on nettles early in the season for example, and blue tits are attracted to the garden to eat the aphids too.
Nettles can spread easily, so don’t go over the top. A small patch in a corner will be easily sufficient. Alternatively, grow them in a pot.
2. Create a pond
Frogs and toads are a predator of both slugs and snails and a pond helps attract them. Frogs spend a good amount of time in and around ponds and value them as a space to hide as well as breed.
Toads don’t have quite as much of a need for ponds as frogs but do like the shallower parts for breeding. Even frogs will spend the majority of their time out and about in your garden enjoying the moist, shady spots rather than in the pond. So you don’t have to place the pond near to the vegetable patch necessarily, as long as it’s in your garden.
3. Create lots of shady spots and log piles
Beetles, frogs and toads all spend most of their time in damp, shady spots. They venture out to feed and then return to the shade for safety and to stay cool and moist. Long grass, log piles, and stone piles all create great conditions. Hedges are also very good for ground beetles, who like to live at the bottom of them.
4. Plant flowers to attract predators
Yarrow, Dill, Fennel, Golden Marguerite and Coriander all attract Lacewings, Labybirds, Hoverflies and Parasitic wasps, which eat the nectar. Inter-plant these with your vegetables, fruit and anything else you want to protect to attract the predators to where you want them.
5. Attract birds
Attracting birds like Tits to nest in your patch means you will have a dedicated pair of parents hunting throughout your garden to feed their young, working through your pests as they go.
Bird boxes are a great start. Bat boxes are also worth installing as bats are wonderful evening devourers of moths, which lay eggs that produce caterpillars.
Bird food, ponds or bird baths for drinking water and shrubs and hedges for shelter and protection also help to make birds feel at home.
All in all
The less welcome visitors to your garden are living wild things and deserve our respect as much as the blue tits and frogs do. Creating a system in your garden where predators have things to eat and less welcome visitors can exist in balance. creates a system that works long term. A garden with none of these unwanted visitors is a garden where none of these predators can find food.
Everything out there is inter-acting with everything else. We don’t want to focus on wiping things out altogether, but creating equilibrium. Working with our patch to create a balance between eaters of our precious plants, and eaters of those eaters, creates the best chance of getting to a point where it’s less about war, and more about harmony.