What picture do Belgian trial harvesting figures paint?

Fiwap, Carah, PCA and Inagro jointly took samples from 27 Fontane plots. These are spread over 11 fields in Wallonia and 16 in Flanders. 17 Bintje plots were also sampled, spread over both parts of the country.

The potatoes were planted in April, but were planted on time on average. That is about 1 week earlier than last spring. As a result, the Fontane's have had 100 growing days and the Bintje plots have had 97. Last year the number of growing days in this period was 86 and 87 respectively. This is approximately the same as 2017.

Fontane yield high level
The Fontane's samples average 33 tons per hectare (gross). It is striking that Flanders, with an average of 38 tons per hectare, does better than Wallonia, where the Fontane's do not exceed 27 tons per hectare. This makes the average 20% higher than in the previous 4 years. The multi-year average is 27,5 tons per hectare. The percentage 50 millimeters upwards is average at 50%, just like an underwater weight of 385. The tuber number is slightly lower.

In Flanders, the plots with Fontane are slightly more outdated; The foliage is on average 20% outdated and in 25% of the plots this is even 30% or more. How are the plots faring now? If we look at the multi-year growth curve, it is visible that the first sampling scores slightly above that. Last year the potatoes gave up early and growth was slow. Scattered 15 to 45 millimeters of rain fell in Belgium last week, but it remains very dry. In 2017, the crops continued for a long time and a top yield was achieved. This year will probably be more like the 2016 line, which ended at 45 tons.

Figures from Bruwier
Potato trading house Bruwier also sampled their Fontane plots in week 31. This results in a net yield of 30,2 tonnes per hectare, with more than half 50 millimeters upwards and an underwater weight of 388 grams. This figure is 17% below the 5-year average of 36,5 tonnes. However, the yield is better than last year. Then 28 tons were sampled in week 28.

Bruwier no longer samples Bintje, because this variety is losing enormously in area and sales. Instead, Challenger is sampled. The first result is 29 tons per hectare, with only 32% 50 millimeters or coarser. The samples contained 3 tons of undersize. According to Jan van Luchene, from Bruwier, this is due to 2 problems. On the one hand, some plots had significant attendance problems. On the other hand, it is very dry in the province of Hainaut, where most of Bruwier's Challengers are located.

Bintje is underperforming
PCA and Fiwap are still sampling Bintje plots. These results amount to an average of 27 tonnes per hectare net. Only 32% are 50 millimeters or coarser and the underwater weight averages 377 grams. This means that the first Bintje yield is almost equal to the 5-year average of 27,4 tons.

Of the Fontane samples, only 1 plot had perennial growth. With Bintje it's a different story. On 4 plots, 20% or more of the tubers were damaged by overgrowth. Since sampling took place quite soon after the rain, the researchers expect more flushing to occur. Bruwier reports that all their Bintje plots are experiencing overgrowth. In Flanders there are 7 plots of which 20% of the foliage has died.

What conclusions can be drawn?
It is difficult to draw firm conclusions from these figures. There are 2 major uncertainties involved. How much precipitation is left in the barrel and what effect has the heat had? Rainfall in Belgium is very widespread. Not enough falls have occurred everywhere. Moreover, it was and remains dry. The high temperatures have certainly hit the crop and Bintje is plagued by overgrowth. Not all parties are coarse enough to apply MH/Fazor.

Although the foliage of various crops is still green, most crops are outdated. Also the later Fontane's. The predicted rain for week 32 has now largely shifted. It is limited to a few millimeters, but with a somewhat moderate temperature. Slightly more precipitation is expected in Wallonia than in Flanders, but also in combination with higher temperatures.