Gardeners are increasingly using living pest controls as an eco-friendly way to care for plants – but some companies in a Gardening Which? test sold duds.
Gardening Which? found that 44 per cent of the biological pest controls it tested didn’t live up to their promises, and uncovered wide variation in the quality of products from different suppliers.
Mail-order firm Agralan was most consistent for quality, and was one of the cheapest suppliers on test. Its insect pest control products performed particularly well in tests for red spider mite and whitefly control.
Products from Biowise performed worst overall, with five out of the six whitefly controls deemed to be unacceptable – in two orders no bugs at all hatched and most of the red spider mite control products contained fewer bugs than promised.
Defenders was rated best for its biological control for slugs, but both the whitefly and red spider mite controls contained less viable bugs than claimed.
Similarly, the tests, conducted in July this year, found Scarletts red spider mite control contained the expected amount of bugs, but four out of the six slug controls didn’t contain the expected number of parasites.
Ceri Thomas, Editor of Gardening Which?, said: ‘Gardeners are always on the look out for ways of dealing with unwanted pests, and biological controls are a great way of doing it without the use of chemicals. However, they are pretty pricey and most are too small to see with the naked eye, so buying them is a big leap of faith – and as our tests show, the results can really vary.
‘We hope that the suppliers who performed badly in these tests will take a good look at their quality control so that gardeners can be assured that they when they buy these products they are are getting what they’re paying for.’