Re-creating a Washington Farming Experiment

George Washington often used experimental methods to advance agriculture at his Mount Vernon estate. Realizing that cultivating tobacco depleted his soil, Washington switched to growing grains, namely wheat, oats, and barley. Always seeking better results in his harvest, in 1760, he conducted an experiment to discover the best fertilizer mix for these grains.

After reading journal entries about this experiment, Mount Vernon’s Historic Trades staff re-created the test at the Pioneer Farm using the same mixtures: cow manure, horse manure, sheep manure, creek mud, and river sand dredged from the Potomac River. The staff followed the instructions in Washington’s diary entry from April 14, 1760:

“All mixd with the same quantity & sort of Earth in the most effectual manner by reducing the whole to a tolerable degree of fineness & jubling them well together in a Cloth. In each of these divisions were planted three Grains of Wheat 3 of Oats & as many of Barley, all at equal distances in Rows & of equal depth (done by a Machine made for the purpose).”