Potato growers need to be extra careful when controlling potato volunteers in drought-stressed crops, Dow AgroSciences has warned.

The firm’s Fazor (maleic hydrazide) – the only in-crop solution for volunteer control – should not be used on crops that are suffering moisture stress or pest or disease attack, explained principal biologist, Andy Leader.

“Also it should not be applied when temperatures are above 26C. Even irrigated crops should only be treated when the temperatures have fallen in the evening.”

Ideally the product should be applied five weeks before harvest when the crop is actively growing, with the bottom leaves starting to senesce, he said. “Each field should be checked for maturity and tuber size by using test digs. Marketable tubers must be at least 25mm across.”

To help growers optimise volunteer potato control and sprout suppression, Dow AgroSciences has launched a web-based Fazor training module, available at www.fazor.co.uk

Those completing the module will be entitled to one CPD BASIS point.