UK gardeners can buy beneficial insects, predatory mites and microscopic nematodes to help control many common garden, greenhouse and houseplant pests naturally.
At Natural Grower, we believe pest control should work with nature rather than against it.
Our Natural Pest Control range includes biological controls for problems such as fungus gnats, vine weevil, leatherjackets, slugs, aphids, whitefly, red spider mite and thrips.
The important thing is choosing the right biological control for the pest you actually have.
What are biological pest controls?
Biological pest control uses naturally occurring organisms to target particular garden pests.
These can include beneficial nematodes, which are microscopic organisms used to control susceptible pest stages in soil or compost, as well as beneficial insects and predatory mites that feed on pests living on plants.
Rather than reaching immediately for a broad-spectrum pesticide, biological control allows gardeners to take a much more targeted approach.
It's a way of dealing with a pest while supporting the wider, living ecosystem of your garden.
Which natural pest control do I need?
Correctly identifying the pest is the first step.
| If you have… | Biological control to consider |
|---|---|
| Fungus gnats / sciarid flies | Fungus gnat nematodes; nematodes + yellow sticky traps |
| Vine weevil | Vine weevil nematodes |
| Leatherjackets | Leatherjacket nematodes |
| Slugs | Slug-control nematodes |
| Aphids | Ladybirds or lacewing larvae |
| Whitefly | Encarsia |
| Red spider mite | Phytoseiulus or suitable predatory mites |
| Thrips | Suitable predatory mites and/or nematodes depending on the pest lifecycle and growing conditions |
Biological controls are living products, so availability, application timing and suitable temperatures can vary throughout the year.
Always check the individual product instructions before ordering and applying a treatment.
Browse Nematodes & Beneficial Insects
Why use biological pest control?
A healthy garden isn't a pest-free garden.
Aphids, slugs, caterpillars and many other insects form part of a much larger food web, providing food for birds, hedgehogs and other wildlife.
Sometimes, however, one particular pest becomes numerous enough to damage plants.
That's where biological controls can be particularly useful.
Instead of treating everything in the garden, you can target the pest causing the problem.
For us, that's a much better fit with organic and wildlife-friendly gardening: intervene when you need to, but work with the natural balance of the garden wherever you can.
What are nematodes and how do they work?
Nematodes are microscopic organisms that occur naturally in soil.
Different species and strains target different pests, which is why there isn't one universal “garden nematode”.
Beneficial nematode products contain nematodes selected to target particular pest species or life stages. They are generally mixed with water and applied to the soil or growing medium, where they seek out susceptible hosts.
This means that choosing the correct nematode matters.
A treatment designed for vine weevil, for example, shouldn't simply be assumed to be suitable for every other soil-dwelling pest.
Temperature and moisture matter too, so always follow the instructions supplied with the particular product.
How can I get rid of fungus gnats naturally?
Those tiny flies hovering around houseplants are often fungus gnats, also known as sciarid flies.
The adults are the flies you notice, but the larvae live in the growing medium. That means successful control works best when you think about the whole lifecycle.
A simple approach is:
- Make sure they really are fungus gnats. They can easily be confused with fruit flies.
- Avoid keeping the surface of the compost continually wet. Fungus gnats favour moist conditions.
- Use yellow sticky traps to catch and monitor adult flies.
- Apply fungus gnat nematodes to target susceptible larvae in the growing medium.
- Continue monitoring. A heavy infestation may need further treatment in accordance with the product instructions.
Using sticky traps and nematodes together targets different stages of the lifecycle.
Shop fungus Gnat Treatment bundle
Can beneficial insects control aphids?
Yes. Aphids have several natural predators, including ladybirds and lacewing larvae.
Rather than spraying an entire plant, introducing an appropriate beneficial predator can provide a more targeted way of managing an aphid infestation.
The best choice will depend on where you're growing, the time of year and the severity of the problem.
In an outdoor garden, it's also worth encouraging naturally occurring predators by growing a range of flowering plants and creating habitats for insects and other wildlife.
Sometimes nature is already doing more pest control than we realise.
Can biological controls be used in an organic garden?
Biological pest control fits very naturally with an organic approach because it allows gardeners to manage particular pests without automatically reaching for synthetic chemical pesticides.
However, individual products can have different approvals and instructions, so check the specific product information if formal organic approval is important to you.
This is particularly important because “natural”, “biological” and “approved for organic growing” don't necessarily mean exactly the same thing.
How to get the best results from nematodes and beneficial insects
Because biological controls are living organisms, they need slightly more care than a bottle of conventional garden treatment.
Order when you're ready to use them.
Some biological controls have a limited storage life.
Check storage instructions as soon as they arrive.
Nematodes may require refrigeration and should never be frozen unless the manufacturer's instructions specifically say otherwise.
Pay attention to temperature.
Different nematodes and beneficial insects work best within particular temperature ranges.
Keep soil conditions suitable.
Nematodes need moisture to move through the soil or growing medium, so application and aftercare matter.
Treat the right area.
For soil-dwelling pests, make sure the treatment reaches the root zone or area where the susceptible pest stage is living.
Be careful with other pesticides.
Some pesticides can also harm the beneficial organisms you're introducing. Check compatibility before combining treatments.
And most importantly: identify the pest before treating it.
What about slugs?
Slugs are another pest where we prefer a considered approach rather than trying to eliminate everything from the garden.
They play a role in decomposition and are an important food source for wildlife, but they can also cause significant damage to vulnerable young plants.
Slug-control nematodes can be useful when conditions are suitable.
Around particularly vulnerable seedlings, our raw sheep's wool mulch can also be used as part of a natural approach to protecting plants, while helping retain moisture and eventually adding organic matter back into the soil.
Why Natural Grower stocks biological pest controls
Natural pest control is a natural extension of the way we already think about gardening.
Healthy soil supports healthy plants. Healthy gardens support wildlife. And when intervention is necessary, we would rather help gardeners choose something targeted and appropriate than automatically reach for a broad-spectrum chemical treatment.
That's why alongside our own organic compost and fertilisers, we've brought together biological controls and other carefully selected products that complement the Natural Grower approach.
Love your soil. Nurture your plants. Grow organically.
Frequently asked questions
Can I buy ladybirds for aphid control in the UK?
Yes. Live ladybirds and other beneficial insects can be supplied to UK gardeners when seasonal conditions are appropriate. Check current availability before ordering.
Do nematodes work for fungus gnats in houseplants?
Beneficial nematodes can be used to target susceptible fungus gnat larvae living in the growing medium. Yellow sticky traps can be used alongside them to monitor and catch adult flies.
Do nematodes kill all garden insects?
No. Different beneficial nematodes target particular hosts, which is one reason correct pest identification and choosing the appropriate product are so important.
Are biological pest controls safe for an organic garden?
Biological controls can form part of an organic approach to pest management. If you specifically require a product approved for organic growing, check the certification and product information for that individual treatment.
When should I apply nematodes?
It depends on the type of nematode and the pest being treated. Soil temperature, moisture and the lifecycle of the pest can all affect when treatment will be effective. Follow the instructions for the individual product.
Why are some beneficial insects or nematodes unavailable at certain times?
They are living biological controls, and some are only appropriate to supply or release when temperatures and seasonal conditions are suitable. Availability can therefore change throughout the year.
Can I use pesticides at the same time as beneficial insects?
Some pesticides can harm beneficial insects, mites or nematodes. Check the compatibility information for both products before using them together.
Find the right natural pest control
The first question isn't “What can I spray?”
It's “What pest do I actually have?”
Identify it first, understand where it is in its lifecycle, and then choose the most targeted treatment.
That's a more natural way to protect your plants — and the wider life in your garden.
Shop Natural Pest Control · Shop Nematodes · Shop Beneficial Insects · Shop Sheep's Wool Mulch
Last updated: September 2026
