Greg Hemphill is a 5th generation operator running four farms. He owns 280 ha and leases 80, and grows potatoes for seed on the farm we visited; 80 ha of potatoes and 80 of oats. In the 1990’s he was producing 28 t/ha. Now it is 33.6-39.2 t/ha, a 20-40% increase. Greg has used the Albrecht-Kinsey system for six years and has noticed quality improvements as well. He spends between $4,000 and $5,000/ha on fertiliser, and reports his customers are very happy with the results they get.

In his first year, Greg divided a 10 ha field into three parts; one-the usual, two-Albrecht-Kinsey, and a third with a different brew. The best result was the Albrecht-Kinsey system as recommended by Alan. Some of the quality differences were better storage characteristics and elimination of hollow-heart.

Greg’s oats also showed marked improvement, increasing by 60% from 1,900 kg/ha to 3,050 kg/ha. The bushel weight for oats is 34 lbs, with the lightest weight being 12 lbs; Greg’s weigh 37 lbs and are sold to Quaker Oats to be used in flour, baking and porridge. Last year was a bad year with his neighbours’ yields suffering. Greg still harvested 3,050 kg/ha.

The soil has improved and is still improving; this year is a dry year, but it has still held its moisture. Potato yield is the sum of the number of plants/ha, the number of tubers/plant, and the size of each tuber. Potassium drives this equation, so the correct type of potassium and the correct amount of K to be applied according to the soil test is critical to success. Part of this success is mounding just once, at 40-50 days after planting.

One of Greg’s soil tests on a newly leased block looks similar to a NZ one, with the exception of high copper. The soil needs inputs of nitrogen, sulphur, calcium, magnesium, potassium, boron, manganese and zinc, but no phosphate. This field will be going into grain followed by potatoes.