The whole of Mount Vernon continued to be cultivated as before until the last year of his life when he rented Dogue Run Farm to his nephew, Lawrence Lewis.
As a public man he was anxious to improve the general state of American agriculture and in his last annual message to Congress recommended the establishment of a board of agriculture to collect and diffuse information and "by premiums and small pecuniary aids to encourage and assist a spirit of discovery and improvement." In this recommendation the example of the English Board of Agriculture and the influence of his friend Arthur Young are discernible.

It would have been well for the country if Congress had heeded the advice, but public opinion was not then educated to the need of such a step and almost a century passed before anything of much importance was done by the national government to improve the state of American agriculture.
In farming as in politics Washington was no standpatter.

Notwithstanding many discouragements, he could not be kept from trying new things, and he furnished his farms with every kind of improved tool and implement calculated to do better work.

At his death he owned not only threshing machines and a Dutch fan, but a wheat drill, a corn drill, a machine for gathering clover seed and another for raking up wheat.

Yet most of his countrymen remained content to drop corn by hand, to broadcast their wheat, to tread out their grain and otherwise to follow methods as old as the days of Abel for at least another half century.
He was the first American conservationist.