Overview
- Boxtree caterpillars have become common across England and reached the rest of the UK and Ireland, and they can strip a hedge or box plant in less than seven days with silvery webbing and lifeless foliage.
- Sai Nursery advises a potent mix of crushed chilli, garlic cloves, dishwashing liquid, vegetable oil and turmeric in water to deter caterpillars.
- The Little Veggie Patch Co recommends a soapy spray of 1 tablespoon biodegradable dishwashing liquid plus 1 teaspoon cooking oil per litre of water, while Maroochy Sand and Gravel suggests 500ml water with two tablespoons garlic powder and 1 teaspoon washing‑up liquid.
- Gardeners should spray both leaf surfaces—especially undersides—coat damaged areas thoroughly and may apply the mixtures directly to live caterpillars; the soapy recipe can be kept for about a month if stored and shaken before use.
- The Royal Horticultural Society backs concerns about the pest’s spread, and using these home remedies offers a cheaper, lower‑impact alternative to strong chemicals that can help protect topiary and hedges if gardeners act quickly.