December 26, 1806

McMahon Asks for Seeds

Philadelphia Decr. 26th. 1806

Dear Sir

It is painful to me to trouble you at this period, when you are so much occupied with the important affairs of the Nation; but your goodness I hope will excuse my anxiety, to procure some seeds of the indiginous plants of the western parts of America, if you received such from Capt. Lewis on his return. A small portion of every kind you could conveniently spare, would greatly oblige me and perhaps, render me essential service; and it would be of some importance to get them as soon as you could make it convenient to have them forwarded, that each kind might be treated according to its apparent nature, and different methods tried to effect its successful propagation with the greater degree of certainty, especially, the nondescripts, if any.

I have the happiness of being with great respect and esteem, Sir Your sincere Wellwisher.

Bernd. McMahon^[1]Bernard McMahon to Thomas Jefferson, Founders Online, National Archives, founders.archives.gov/documents/Jefferson/99-01-02-4754, accessed 5 January 2026. For a discussion on the botanical aspects of … Continue reading

Bernard McMahon (c. 1775–18 September 1816) is often called “America’s Pioneer Gardner”. Starting in 1806, he published The American Gardener’s Calendar: Adapted to the Climates and Seasons of the United States, the most comprehensive gardening book in America at the time. The preface of the 1806 edition opens:

THE general utility of HORTICULTURE) or the Art of improving every kind of soil; of producing a plentiful supply of wholesome vegetables and fruits, so necessary to health in all countries, especially in warm climates; of cultivating the various plants designed by INFINITE GOODNESS, to minister to the comforts of animal life, by correcting the divers maladies to which it is subject by nature, and still more so, in the human race, by intemperance; of raising many articles of luxury and commerce, as well as materials for ornamenting the whole face of the country; is too obvious, to render any arguments necessary in favour of an attempt to facilitate the general acquisition of that useful branch of knowledge;^[2]Bernard McMahon, The American Gardener’s Calendar: Adapted to the Climates and Seasons of the United States (Philadelphia: B. Graves, 1806), archive.org/details/americangardene00mmagoog/.

McMahon helped Thomas Jefferson plan his Monticello garden and was the one who recommended Frederick Pursh to classify and illustrate the yet-to-be published journals of the expedition.

Splitting the Seeds

Washington Jan. 6. 07.

Sir

I recieved in due time your letter of Dec. 26. but it has been impossible for me to answer it sooner. Capt Lewis has brought a considerable number of seeds of plants peculiar to the countries he has visited. I have recommended to him to confide principal shares of them to mr Hamilton of the Woodlands & yourself, as the persons most likely to take care of them, which he will accordingly do. he will carry them on to Philadelphia himself.

Th: Jefferson^[3]Thomas Jefferson to Bernard McMahon, Founders Online, National Archives, founders.archives.gov/documents/Jefferson/99-01-02-4818 accessed 5 January 2026.

The Woodlands became one of the nation’s most renowned botanical resources. At its height, Hamilton’s impressive plant collection contained approximately 10,000 species of native, foreign, and rare plants. When Jefferson retired in 1809, some of the plants grown from Lewis’s seeds were sent to him were planted in his Monticello gardens.^[4]“Seeds from the Lewis & Clark Expedition”, Thomas Jefferson Center for Historic Plants c. 2005. See also on this site The Woodlands