Corn roots can grow quite deep, typically reaching depths of 3 to 5 feet (36 to 60 inches) under favorable conditions, with some roots even extending to 6 to 7 feet (72 to 84 inches) in certain cases

. The root system consists of a dense network in the top 12 inches of soil near the plant, with main horizontal roots spreading 18 to 42 inches outward before turning downward

. The deepest roots usually penetrate vertically downward, spreading about 12 to 18 inches from the base of the plant, filling the soil volume to depths of 3.5 to 5 feet or more

. Corn roots grow rapidly during vegetative development, especially from the 4th leaf stage to silking, with an average growth rate of about 2.75 inches per leaf stage, reaching a maximum depth of around 60 inches (5 feet) in typical field conditions

. Root depth can vary depending on soil type, moisture, oxygen availability, and genetics; for example, roots may not grow as deep in wet or compacted soils due to lack of oxygen but tend to grow deeper in sandy or well-aerated soils

. Most moisture uptake occurs in the top three feet of soil, although roots can extend deeper if conditions allow

. In smaller-scale or container gardening, corn roots typically have an effective depth of about 30 centimeters (approximately 1 foot), but in field conditions, roots can be much deeper

. In summary, corn roots generally grow 3 to 5 feet deep, with potential to reach 6 to 7 feet depending on environmental and genetic factors