If the trial harvest figures of this season teach us one thing, it is that there is an enormous variation in yields. The kilos of potatoes planted on time are a lot lower. The late planted potatoes still have a while to go before they reach an average yield. Unfortunately, the clock is ticking relentlessly.
The current late summer weather makes you almost forget that it is already mid-September. For many growers, this is usually the time to spray the later potatoes to death. Waiting longer is possible, but then you also postpone the harvest moment with the associated risks. Many varieties need between 100 and 150 growing days. Potatoes that were planted in the first half of June are only now at 100 growing days.
Every kilo you can gain by waiting to spray is a bonus. If there are only a few kilos left - as is often the case with late-planted potatoes - those extra kilos may be even more important. The costs per hectare divided by 45 or 50 tons makes less of a difference than dividing by 25 or 30 tons per hectare, while in both cases it is an extra 5 tons. The aim to keep the potatoes green for as long as possible is therefore easy to understand.
Waiting should be possible
The next question is whether the soil can handle that. The fact that the potatoes were planted so late on some plots is not out of luxury. The higher plots, which are well-drained, without low spots and which were not destroyed last season by, for example, harvesting beets, were the first to be planted this spring. Of course, the rain this spring was very local in nature and, certainly as a large grower, you cannot be everywhere at the same time, but in general, it is not the best plots on the farm that were planted last.
Forecasting the weather for a week is already difficult for the various weather services, let alone the weather for a month from now. The weather can be good at the end of October or the beginning of November, but if it rains, it dries out less. The soil simply works less. If the soil was not so good in the spring, you can reasonably expect that it will not improve much in the fall. Late harvesting, a mediocre structure and then also fewer potatoes in the bed is the recipe for a challenging harvest. Trial harvests and growth curves are fun, but in the end it is all about getting the potatoes out of the ground. In that respect, for the late planted potatoes it is a bit of a choice between two evils.