Farmers sowed 9300ha of what they believed was yellow-fleshed Hawkstone Cleancrop brassica for winter feed but were actually supplied HT-S57 brassica, which in 2014 was responsible for toxicity issues in cattle and sheep.
PGG Wrightson Seed manager David Green said farmers were given a product they did not want to buy so it is right that they should be refunded.
Farmers will be refunded the cost of seed and chemicals sold as a package.
“From our perspective, we are really disappointed that this happened and we want to make sure we do the right thing.”
Green was reluctant to say how much the refund would cost but sources estimate the establishment cost was more than $200 a hectare, meaning the total refund cost to the merchant is more than $2m.
All 556 farmers who bought the seed have been contacted, with 160 registered with PPG Wrightson and the rest through seed retailers.
A designated response team has also been established to help farmers manage the crop, especially in late winter when there can be palatability issues.
The 2014 winter was especially mild and it was discovered that contributed to the HT-S57 brassica beginning the reproduction stage earlier than expected.
The toxins it produced caused death and health issues in some stock, especially dairy cows that had returned home from winter grazing and were held on swede crops before calving.
Green said the two varieties produce identical drymatter but human error caused the variety mix up during the supply chain process.
Green will attend a public meeting called by Clutha Southland National Party MP Hamish Walker in Gore on April 6.
The meeting will update farmers on animal health precautions and will be addressed by PGG Wrightson, DairyNZ and Beef + Lamb NZ.
