Regrowth kills Fontane and Challenger yields

On 75% of the 31 plots with Fontane, the haulm killing had already taken place during the last trial grubbing on September 21 or 22, with the start of haulm killing around September 13. The total yield has hardly increased between the last 2 trial harvestings and in the third week of September averages 46,4 tons per hectare, which is still well below the multi-year average (2014-2019) of 51,9 tons.  

Major differences between plots Fontane
During the first trial harvest A lower yield was already noted and that arrears ultimately proved impossible to make up for. This is because the re-growth was slightly slower than normal throughout the season and the gap between the current yield and the multi-year result became larger and larger. It is striking that the regrowth between 7 and 21 September can be called fairly normal: 150 kilos per hectare per day.

What is also striking is that the spread between the potato plots is considerable. The lowest yield for Fontane is 24 tons, while the highest results are above 55 tons per hectare. A comment should be made in this regard: this only concerns the irrigated plots. The difference between Flanders and Wallonia has remained constant throughout the season. In Flanders, the average yield was 50 tons higher than in Wallonia (42 tons).

In the end, the coarseness also came out finer than the 6-year average. The average for Belgium is 38,5 tons in the order of 50 millimeters upwards, while the average is 41,3 tons. In percentage terms, however, 82% of the yield is in this sorting, compared to an average of 80%. The underwater weight is 416 grams. This is a normal result for Fontane. 

Little regrowth in Challenger
The gross yield of the Challenger plots in mid-September is 42,5 tons per hectare, which is also well below the multi-year average. In the previous 6 years, the yield was on average 51,7 tons. Due to the persistent drought and heat at the end of August, the growth limited stayed. Between 7 and 21 September, the growth amounted to 70 kilos per hectare per day.

The variation between the Challenger plots is less than at Fontane: the difference between the lowest (35 tons) and the highest yield (48 tons) is only 13 tons. In addition to a lower yield, the grading is also fine here: 26,4 tons are 50 millimeters upwards in the size grading. The long-term average is 41 tons. In Flanders this is higher: 30 tons versus 22 tons in Wallonia. The underwater weight is stable at around 442 grams, which is about 30 grams more than the average of previous years.