(i) Temperature : Cool and moist weather during growth, and warm and dry climate during ripening is needed. (ii) Rainfall : 50-75 cm rainfall is required. Rainfall is necessary and beneficial, 15 days after sowing, and 15 days before ripening. A few light winter showers or assured irrigation ensures a bumper harvest. (iii) Soil : Light domat (loamy) soil is required. It can also be grown in black soil. Important producers : Punjab, Haryana, western Uttar Pradesh and Madhya Pradesh are the main producers of wheat.