In the 2025-2026 cropping season, the fourth summer of the Carbon Positive trial, we are growing butternut pumpkins for Heinz-Wattie’s. Our planned planting date is the middle of November.
In the Conventional system, things are getting underway with a broadcast spray of glyphosate now that the sheep have been moved out. The paddock will be cultivated in early November and planted with butternuts. Fertiliser applications, including planting and side-dressing, will be at full fertiliser rates that are typical on the Heretaunga Plains.
The Hybrid system was strip-sprayed in mid-September and will be strip-tilled about three weeks before planting. Two weeks before planting, it will be broadcast-sprayed to clean up the remaining cover crop outside the strip-sprayed zone. We may spray about three days after planting if weeds or cover crop regrowth are an issue. Fertiliser applications, including planting and side-dressing, will be guided by soil results.
The Regenerative system was also strip-sprayed in September, and the plan was to avoid cultivation. However, grazing sheep have compacted the soil, so strip-tilling is our back-up plan. Two weeks before planting, it will also be broadcast-sprayed to tidy up outside the strip sprayed zones. Glyphosate will be used to knock back the ryegrass, but clovers and vetch will be left as companion crops. As with the Hybrid system, a clean-up spray may be needed three days after planting. Fertiliser rates will be set according to soil test results.
We will determine weed management tactics as we go but are anticipating that a stale seedbed approach and favourable weather may do most of the work. Our strips will allow the precision weeder to operate if necessary, and there’s a manual fallback we prefer not to think about just yet!
Throughout the season, the Operations Advisory Group and Heinz-Wattie’s agronomists will meet weekly to track how the butternuts are growing. Together, they’ll make the calls on crop protection, weeding, fungicide and insecticide use, and adjust management decisions as the season unfolds.
We are particularly grateful to Heinz-Wattie’s, Gareth Holder from Redloh Horticulture and Hamish Thomas from NH Packing for their support. We look forward to working with them as our butternuts are sown, grown and harvested! Carbon Positive is a partnership between LandWISE, the HB Future Farming Trust, McCain Foods, Heinz-Wattie’s and Process Vegetables NZ.
Many thanks to our sponsors
