Box tree caterpillars can quickly devastate your prized box hedges, stripping leaves and leaving unsightly bare patches. Without intervention, these hungry pests can even kill the plant. Gardening Naturally box tree caterpillar nematodes are a natural organic pest control designed to reduce box tree caterpillar damage in planted beds, borders and vegetable plots. The nematodes are microscopic transparent worms that live in the soil and feed and multiply inside the box tree caterpillars that they come into contact with. These nematodes are a mix of Steinernema feltiae and Steinernema carpocapsae. Unlike synthetic pest control options, these highly specific natural predators will hunt day and night to protect your vegetables from unwanted intruders while leaving other beneficial insects alone.

How does it work?

Nematodes naturally occur within soil in the UK, but in low numbers. By adding more of these box tree caterpillar-specific nematodes, you can quickly reduce box tree caterpillar populations. When they come into contact with a box tree caterpillar, they enter through natural openings and feed and multiply. Within days, the box tree caterpillar will stop eating, and within a week, it will die. The nematodes will multiply and spread out in the soil, seeking more box tree caterpillars to continue to propagate. Most of this occurs below the surface.

How do I identify box tree caterpillars?

These pests are the larvae of the box tree moth, hatching from eggs laid beneath leaves. Young caterpillars are green-yellow with black heads, maturing into striped black-and-white larvae. Look for chewed foliage and silky webbing—clear signs of an infestation.

How do I use them?

Gardening Naturally nematodes are supplied as a dry powder which can be mixed with water in a watering can and then applied to the area you want to protect. We advise applying them when the caterpillars are most active between March and October. Once applied, try to make sure that the soil doesn't completely dry out to ensure that the nematode population remains healthy and strong.

Is it safe?

Nematodes are completely natural and prevalent in most gardens throughout the UK. Gardening Naturally predatory nematodes are simply a more precise and effective version, which will only target the local box tree caterpillar population. They are designed for use where pets and other wildlife are present,

When is the best time to use Nematodes?

The best time to use these nematodes would be when the soil temperature is reliably above 5°C, and the box tree caterpillars are active, usually by the end of March through to October. The nematodes can be applied multiple times throughout the year to make sure the colony remains active. 

Application Advice:

1. Dissolve the entire contents of the first sachet in a bucket containing 2.5L of water to create a solution.
2. Stir vigorously and then take the solution and add a further 4.5L of water before transferring this mix to a watering can or sprayer.
3. Use this mix as a foliar spray, making sure the solution covers the pests. We advise starting from the bottom and working your way up, making sure the centre of the plant is covered. This 7L solution can cover an area up to 30m²
4. After 5-7 days, repeat steps 1-3 with the second sachet. The nematodes can be stored for up to a week in the fridge.

In total, you should go through 14L of water and cover a 30m² area twice.