Haulm destruction and harvest
Haulm destruction before harvesting is often applied to reduce damage at harvest. Before harvesting haulm is pulled, cut or killed using chemicals. The method used has an effect on:
- possible skin damage
- regrowth and virus infection
- black scurf (Rhizoctonia) on the tuber
HAULM DESTRUCTION METHODS
Time of haulm destruction
In general haulm destruction takes place 10-15 days before harvest. It is evident that a good skin formation after haulm destruction is quicker in a crop which is close to maturity, than in a crop which is still in full production. A more mature crop can be harvested sooner after haulm destruction than an immature crop. The harvest method used also strongly influences the period needed between haulm destruction and harvesting. With manual harvesting methods this period can be short (often a few days are sufficient).
Timing of harvest
Table potatoes are in general left in the field until maturity. An early harvest of the crop (before maturity of the crop) gives as a result a relatively low yield of the crop, relatively small tubers, a relatively low dry matter content of tubers and a high content of reducing sugars.
In seed production an early harvest is common practice . This to reduce the risk of infections with especially virus diseases and to harvest a high percentage of seed sized tubers. The early harvest results in a relatively low total tuber yield. This low yield is a main reason for the high production cost of seed.
MATURITY AND TIMING OF HARVEST