Higher rate Retro targets tough weeds

A new approval for the contact herbicide Retro will enable potato growers to use up to 4.0 l/ha this season – a doubling in the highest permitted rate. The new treatment will give more robust control of larger and more difficult weeds, to leave a clean seedbed for rapid emergence, reports Syngenta Technical Manager, Glenn Wilkinson.

"The higher rate will be valuable for growers who wait until as close to emergence as possible before applying their residual herbicides, when there may already be significant weed populations established," he said.

Mr Wilkinson highlights that for the past two seasons growers have achieved the best results with Defy mixtures applied at or around the time of crop emergence. "Defy is the most crop safe of the residual herbicides, but with mixture partners it is essential to include Retro in the tank to burn off established weeds and assure minimal effects on the crop for fast establishment," he advises.

He adds that with only reduced rates of linuron now permitted, most growers will want to wait until as close to emergence as possible to ensure they get the best possible residual activity, making the role of Retro especially important. The new approval is targeted specifically at Black Bindweed, Cranesbill and other difficult to control weeds.

The new approval is only applicable to Retro and is not permitted for any other diquat herbicide.