Cotton is a high-heat crop that thrives in temperatures between 25°C and 35°C, requiring at least 180 to 200 frost-free days to complete its cycle. It is highly sensitive to cold, and growth will effectively stall if temperatures drop below 15°C. While the plant is relatively drought-tolerant, it requires well-distributed rainfall or irrigation of 500 mm to 1,200 mm annually, with a critical need for water during the flowering and boll-filling stages.

This crop performs best in low to moderate relative humidity, ideally between 40% and 60%, which encourages healthy transpiration and reduces disease pressure. High humidity (above 70%) during the late season is problematic, as it can cause “boll rot” and interfere with the opening of the bolls; additionally, dry weather during harvest is essential to prevent the fiber from becoming discolored or “trashy.”

he ideal soil is a deep, fertile, and well-aerated sandy loam or clay-loam that can accommodate the plant’s powerful and deep taproot system. Cotton is notably tolerant to soil salinity, often outperforming other field crops in salt-affected areas, though it is most sensitive during the germination stage. Excellent internal drainage is necessary to prevent “wet feet” and ensure the roots can access oxygen during the rapid growth phase.

For optimal yield and fiber quality, maintain a slightly acidic to neutral pH between 5.8 and 7.5. While cotton is rugged regarding salinity, it does not perform well in highly acidic soils; if the pH drops below 5.5, the plant often suffers from mineral toxicities or poor nutrient uptake, leading to stunted plants and reduced boll counts.