With temperatures in the vicinity of 40°C, people are not the only ones suffering from the heat: some fruits and vegetables have also been scorched by the sun, and harvests could be affected.
Apples have been hit particularly hard. Depending on the farms and types, between 5% and 10% of cultivars – in some cases even 25% to 30% – have been burnt by the sun. “Generally, the apple is a fruit that does not stand up well to extreme heat,” Olivier Warnier, head of the Walloon Fruit Centre, explained. It’s mainly “apples exposed to the afternoon sun that have been burnt,” he added.
Pears are doing a bit better. According to Warnier, there has been less leaf-scorch than last year.
Where cherries are concerned, harvesting is almost completed, so they have suffered less, even if the heat has dried some late fruits, giving the impression that they are withering, Warnier noted.
“Apricots, for their part, have resisted the heat better because they are fruits from the south of Europe,” he explained
Extreme heat also affects fruit sizes. “We’ll have to wait for another fortnight to see what their final size will be,” Warnier said.
Vegetables grown in greenhouses have also been affected. “Tomato plants were almost cooked or liquified,” said Nicolas Flament, technical adviser at Wallonia’s inter-professional market gardening centre.
“These little greenhouses are very hard to ventilate and the temperatures quickly became unbearable for the workers” who had to harvest the vegetables there. Sweet peppers are also very sensitive to extreme heat and develop brown, damp spots, and can no longer be sold.
Another problem is that the heat dries up vegetable flowers, which prevents them from being fertilised. “There could therefore be a gap in production in about two weeks’ time,” Flament said.
The real impact of the heat wave will only be measurable around mid-August for vegetables, and around harvest time for fruits: late August for pears and mid-September for the main varieties of apples.