Potato growers in the southwest of São Paulo state are completing winter crop planting in line with the regional calendar, but frosts recorded in late June are set to weigh on yields. According to HF Brasil, damage will likely translate into smaller tubers, particularly for crops harvested from August onward, with September expected to show the sharpest impact.

Harvesting began in June and will continue through December, with roughly 60% of volumes expected to reach the market by the end of August. For the lots currently being lifted, quality remains high, though tuber skins have not fully set due to persistently low July temperatures. Limited daytime sunlight slowed crop cycles, while this season’s mild climate—although delaying development—proved less harmful than periods of excessive heat. Low rainfall has also been favourable, given the crop’s reliance on irrigation.

Pest pressure has shifted across planting cycles. Early plantings saw damage from the beetle Diabrotica speciosa (vaquinha), linked to the higher temperatures in February and March. From June, and especially in July, wireworms became the main challenge, as dry conditions and migration from other crops drove infestations. Mid-cycle plants were most affected. Disease issues included cases of common scab, associated with excessive soil liming, and isolated detections of Rhizoctonia solani in late July harvests. These outbreaks were reported as controlled.

By the end of July, average yields stood at 42 tonnes per hectare and are expected to hold steady in the short term. A decline is projected from late August into September as frost damage becomes more visible. With July marking the harvest peak, regional supply is forecast to decrease gradually from August onward.