Sweet clover has a determinate taproot, reaching depths of up to 1 foot, with the ability to affix over 100 lbs. of actual nitrogen. Sweet clover is the most drought tolerant of forage legumes. It is also quite winter hardy and can extract and then release phosphorus, potassium and other micronutrients that are otherwise unavailable to crops. Sweet clover loosens soil structure, creates organic matter, and produces better soil tilth.