GENETICALLY-modified canola could hit a Victorian silo this week with much of the crop windrowed in the Wimmera.

Rupanyup grower Andrew Weidemann has cut and windrowed his canola and expects to harvest it late this week.

"We are hoping to start on Friday or Saturday," Mr Weidemann said, adding that it depended on weather conditions.

Horsham grower Geoff Rethus knocked down his two crops last week and should start harvesting next week.

Mr Rethus grew his canola on a paddock which has had a ryegrass problem and had been cropped and cut for cereal hay over the last two seasons.

"It was amazing how clean (free of weeds) it was," Mr Rethus said.

Mr Rethus said the dry spring and some hot weather would probably affect his yield but the GM canola appeared to have avoided frost damage.

The growers will deliver to Lubeck silo, one of three sites for Victorian growers, with the others at Tatyoon in the Western District and at Finley in southern NSW. GM canola has already been delivered to the Lockhart silo in southern NSW.