When properly cared for, alfalfa can be grown almost anywhere in Iowa with success.
It is quite commonly accepted that this legume is not well adapted in Iowa's climatic and soil conditions and does not fit well into Iowa rotations, but practical experience does not justify this view. The success of many individual farmers and the result of experiments on various soils and under various climatic conditions demonstrate that if proper methods are followed alfalfa can be grown profitably on nearly all Iowa soils.
Hughes, H. D., "Growing Alfalfa in Iowa" (1912). Circular. Paper 3.