Onion (Allium cepa) is an important bulb vegetable crop widely cultivated for its culinary, nutritional, and medicinal value. It grows best in cool to moderate climates during the early stages and requires warm, dry conditions for bulb development and maturity. Onion thrives in well-drained sandy loam to loamy soils rich in organic matter, with an ideal pH range of 6.0 to 7.5. The crop requires moderate rainfall or regular irrigation, as excess moisture and waterlogging can cause bulb rot and poor storage quality. Optimal temperatures of about 13–24°C favor vegetative growth, while slightly higher temperatures support bulb formation. Timely sowing, proper spacing, balanced fertilization, and good drainage are essential for achieving high yield and good-quality onion bulbs.