Fertilize according to soil test results to improve yields. Leaves are pale green or yellowish. The yellowing may affect the new growth or the whole plant, while nitrogen deficiency tends to affect the older leaves first. Sulphur deficiency reduces nitrogen fixation and protein production. Alfalfa will grow poorly on soils when the pH is less than 5.9.
Plants are light green, stunted and stands become thin.
When alfalfa is grown on moderately-acid soil, yields and nitrogen content will be reduced. Apply lime according to soil test results. Applications should be made one to two years before planting alfalfa to allow for thorough incorporation. If lime cannot be applied economically, grow acid-tolerant legumes such as red or alsike clover. Prepared by G.D. Jesperson.