Early August 2026: customers are reporting that a new round of box caterpillars have just re-emerged. This is the 2nd generation (of 3) for this year.
These hungry caterpillars eat the foliage of box plants (Buxus sempervirens). If untreated, after a couple of seasons without leaves, your plants will die, having been too long without foliage. Many beautiful hedges and topiary specimens have been destroyed or, at worst, killed. However, damaged plants can recover quickly if treated correctly.
Luckily, the treatment is easy and cost effective. If XenTari is applied at the correct time, it is very straightforward. There are 3 generations of box caterpillars per year. Box plants should be sprayed with XenTari as soon as you see caterpillars 'grazing' each season.
1) Late May / early June. First season of the year. If you had treated your plants in Spetember / October of the previous year, you would have no caterpillars this season.
2) Early August, Second season. Because of warmth, caterpillars will be greedier than the previous season. Treat with XenTari applied as a spray.
3) Late September / Early October. 3rd and last season. If you treat your plants and kill caterpillars at this stage, you will not have to treat your plants until next August, as there will be no overwintering larvae in your plants.
- Spray healthy, untouched plants as soon as you see any caterpillars nearby.
- The XenTari spray remains effective for approx 2 weeks, once applied, unless it's washed off by heavy rain.
- Once the caterpillars eat a leaf that has psray on it, they will die.
- Use any old spray bottle. One little sachet of XenTari should be diluted with 3 litres of water. 3 litres covers 30 sq metres of plants. So a little goes a long way