The heat of last week has severely affected the early potato parcels in Flanders that PCA follows. The Amora is still doing something while Sinora's growth has come to a complete standstill, according to the results of the trial grubbing-up of Friday 22 July, published by PCA today (Tuesday 26 July).
Since the previous harvesting harvest nine days ago, Sinora has not grown any more kilos. The average yield thus remains at 34 tons per hectare. On one plot (out of eight that are being tracked), the yield remains just under 30 tons per hectare. On most plots the yield is between 30 and 34 tons per hectare. There is one outlier to the top. The yield there comes out at 44 tons per hectare. None of the plots is irrigated. The yield is 105 tons per hectare in the multi-year average after 36 growing days, but because the potatoes are already well ripened, PCA expects that we will soon fall below the multi-year average. 73% of the potatoes, or 25 tons per hectare, are used up in size 50. On average, the plots are already 70% mature. There are, however, significant differences between the plots. A single plot is only 25% ripe, while others are almost completely dead. Compared to previous years, Sinora is only 40% mature on this date.
Amora holds up a little better
The average yield of Amora now amounts to 40 tons per hectare. This means that only 2 tons have grown in nine days. However, the differences between the plots are large. The potatoes irrigated in June achieve an average yield of 47 tons per hectare. For the fields that have not been irrigated, the average yield remains at 36 tons per hectare. On average, 34 tons per hectare or 85% in size 50. The plots that have not been irrigated are 70% to 100% mature. For the irrigated plots, these percentages are between 40% and 75%. The average yield is now 3 tons above the multi-year average on this date and we are still ahead in terms of size. However, the crop has died down further compared to the same period in recent years.
The flattening of the early potato growth curve raises the question of how the main crop withstood last week's heat. PCA writes that the early planted late varieties such as Bintje and Fontane are now also declining rapidly. The plots that are still well green have a good buffering effect for high temperatures, but those plots will also not grow for long if significant rain does not fall soon, according to PCA.
The effective application of MH is also becoming difficult. The crop wears out and because the leaf has hardened, a smooth absorption of the product is made more difficult. Now that the potatoes are deteriorating rapidly, the MH spraying cannot be postponed too long.