Thermophilicity

The tomato is a heat-loving plant native to South America. It grows and produces the best yields at temperatures of about 20–28°C during the day and 16–20°C at night. Prolonged cold spells slow growth, reduce phosphorus uptake, and impair fruit set. Frosts are fatal to tomatoes. In the Polish climate, appropriately selected varieties can yield well in open ground, while a tunnel extends the growing season and stabilizes conditions, but requires ventilation to prevent overheating.