VTA potato harvest trials in The Netherlands confirm low yield expectations

VTA has carried out a test/trial harvest in mid-September under its members according to a set protocol. This yield measurement has been taking place since 2001 and is always carried out at the same time in the year.

Average yield per hectare

The average yield of the samples is set at 47.088 kg per hectare. In 2017 this was 58,507 kg per ha. This means that the yield per hectare is 19.5% lower than the previous season. Compared to the 5-year average, the yield per hectare is 12.5% lower. This is shown in the graph below.

As indicated in the test/trial harvest in August, there were major differences in yield. The lowest was at 21.3 tons/ha and the highest at 84.6 tons/ha. Differences may exist as a result of irrigation or not, and in addition, plots with water damage.

It should also be noted that the majority of the participants are located in clay areas. In the sandy area, the results will also lag significantly behind other years this year. Perhaps even stronger than in the traditional clay areas, but partly due to the large differences in (possibilities for) sprinkling irrigation there are not really hard conclusions to be drawn.

Differences between varieties

Furthermore, there are of course differences between the varieties. Because only a few samples of some varieties had been submitted, it would not be statistically correct to draw firm conclusions here. In calculating the total regrowth, we calculated a weighted average. This amounts to 10.622 kg / ha. On average over the previous 5 years the regrowth in the same period was 10.378 kg / ha.

Regarding the potential of growth, large differences are also reported. For a large number of samples it was stated that the potato plants had already been vine-killed, had already been harvested or was already totally worn out. In contrast, parcels were also reported, with the crop still green.

Tuber size

The percentage tubers larger than 50 mm up is estimated at 61%. In 2017 this was 70%, while the 5-year average is 69%. Again, we see large differences between different plots.

The percentage tubers larger than 50 mm up is estimated at 61%. In 2017 this was 70%, while the 5-year average is 69%.

The average number of tubers in the sample (2 × 3 meters) is relatively low at 178.