This collection consists of correspondence between Harding and French horticulturist Emile Lemoine (1862–1943), along with photographs, manuscripts, and other miscellaneous material. In addition, there is some correspondence concerning Harding after her death between her husband, Edward Harding (?–1952), and various correspondents. The correspondence between Harding and Lemoine refers to their successes in raising peonies. Harding also contributed substantial sums to the Société Centrale Horticulture Nancy, and the award she received for this is described. Letters (ca.98 total) are arranged chronologically.