Potato Review

www.potatoreview.com POTATO REVIEW MARCH/APRIL 2023 45 CROP MANAGEMENT In-season insights Once seed is planted Richard, Farm Manager Matthew Dudley and Agronomist Fiona are out walking crops once a week and this is where Crop4Sight’s in-season insights kick in. ey take stem counts to ground truth the seed module’s forecasts and tuber population predictions are re-run if crop establishment has not been as expected. is aids early decision making, facilitating tweaks to nutrition programmes and target harvest date based on yield potential. It can also bene t Richard’s customers, as in 2021 when some of his crops were hit by late frosts and stem numbers were lower than anticipated. On Crop4Sight, Richard could see tuber numbers were forecast to be low and were likely to result in a much bolder sample of packing variety Jelly than the packer would like. “We supply our potatoes between September and November, andwe could see in June that theremight be a problem. “We were able to have a conversation with Greenvale and pre-warn them. Without Crop4Sight we wouldn’t have been able to prove that with any degree of con dence,” he said. Addressing the issue early meant Greenvale could talk to its customers and subsequently adjust maximum size to 90mm instead of the usual 85mm, helping maintain Richard’s marketable yield and ensure its customers were supplied. Early warning e next step is to enter canopy data. Canopy cover drives the level of light interception fuelling the crop’s biological yield. From inputs of smartphone imagery of the canopy and emergence data, the system forecasts how the cropwill develop. is year, the farm will be trialling the use of satellite imagery to compliment ground level imagery. “It’s surprising the di erence in seed rate we see between planting on April 25th compared to March 25th, particularly when using larger 45-55mm seed. It can be as much as 25% less seed to hit the target stem population.” Richard Maddocks, Wilfred Maddocks Ltd FARM FACTS Wilfred Maddocks Ltd, Chadwell Grange, Newport, Salop • 140ha of potatoes on light sandy soils • Growing for pre-pack and processing markets • Early varieties include Accord and Miranda for chip shop trade • Premiere, Daisy, and Royal are produced forMcCain • Packing varieties Jelly and Tyson go to Greenvale • 1,000t of refrigerated storage e system’s monitoring of actual versus predicted canopy development gives early warnings of potential issues in the eld to adjust management or expectation of yield as the season progresses. Richard says this capability was tested by last year’s unprecedented hot spell, when it picked up that some crops had stopped growing when temperatures spiked above 35C on ve consecutive days. Fortunately, in irrigated crops the actual growth curve didn’t deviatemuch from the prediction and yields were good. But on the 30% that don’t receive irrigation, it was a di erent story, with the canopy going backwards and Crop4Sight predicting a 30% yield drop that was con rmed at second digs closer to harvest. Some may question the value of this information, as it is obvious the heat and drought would have an impact. However, Richard would rather have any bad news well in advance and address it. Crop4Sight gave a picture of what he had across his entire area and reassured him that he was unlikely to end up delivering short of contracts. “As it was so extreme, I did questionwhether the data would be robust, but it was as accurate as it’s always been.” Late season As the season reaches a crescendo and thoughts turn to desiccation, harvest scheduling and maleic hydrazide application, this is where he gets the most out of the system. Although one would expect the earliest planted crops to reach optimummarketable size rst, varietal factors and variability in eld conditions mean this is not always the case. e system tracks crop development, giving Richard forecasts of when they will hit the right size to schedule ailing and stop the crop. is is particularly important in his pre-pack crops, where he is looking for 50%baker content, typically 65-85mm. At the other end of the scale, he needs to eliminate tubers under 45mm, as he harvests straight into boxes and sells crop o the eld, so there is no opportunity to grade themout. “We can programme desiccation and harvest at the back end tomeet our customers’ needs andmaximise our marketable yield. If a crop has been knocked and not going to reach its potential, we can also see that and harvest it early, and, if a crop has thrown a fewmore tubers and needs time to bulk, we can let it run on. “If our landlords want a crop out by a certain date, it helps plan that accurately, too.” ➜ Richard Maddocks of Wilfred Maddocks Ltd.