4R Farming

Michigan Potatoes

This seed potato farm in Michigan grows a diverse rotation with wheat, rye, oats, sorghum, millet, and alfalfa. The farm has very sandy soils and is working to build organic matter. Advanced 4R practices have been used on the farm for 10 years.

Cost decreased from 2017 to 2018 with the change from multiple in-season nitrogen applications with a sprayer to injected nitrogen through fertigation. The amount of nitrogen applied was slightly lower and the cost of the application with fertigation was also lower.

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Changing from basic to more advanced 4R practices the farmer decreased cost per acre by $29.59.

Cost of 4R Implementation for Michigan Potatoes

Yield 425 cwt

Practices Changed from Basic to Advanced

  • Acres are grid sampled and nutrients are applied using variable rate for potassium, phosphorus, and micronutrients.
  • Tissue testing is done on every field every year for secondary and micronutrient needs
  • Fertigation of nitrogen applications on more acres
  • Multiple splits of nitrogen applications in-season – up to six times per season
  • Addition of crops like rye and alfalfa to the rotation for building soil organic matter

Between 2017 and 2018 injection of the UAN28 percent into the irrigation lines was the main practice change. The cost of installing the irrigation and fertilizer injection system was lower than the cost of using equipment to apply in-season UAN28