John Clayton (1694/5–1773) was a Colonial plant collector and botanist in Virginia.
Clayton was born in England and is believed to have moved to Virginia around 1715 with his father, also named John Clayton, who later served as one of the Attorneys General for colonial Virginia. He did not officially show up on any colonial records until October 7, 1720, when he was identified as a clerk in Gloucester County. The site of his home, Windsor, is today located in Mathews County.
He married Elizabeth Whiting, granddaughter of Peter Beverley. The two had three daughters and five sons, one of which was William Clayton, who went on to serve on the Virginia Ratifying Convention. Clayton died, still serving as county clerk, on December 15, 1773.
Clayton explored the Gloucester County region botanically and in 1734 sent many specimens and manuscript descriptions to the English naturalist Mark Catesby, who then sent them on to the Dutch botanist Jan Frederik Gronovius. Clayton would also send work to Gronovius directly.
Unprepared for the amount of material sent to him, Gronovius enlisted the help of the Swedish botanist Carl Linnaeus. However unbeknownst to Clayton, Gronovius would later use much of Clayton's specimen and manuscript work in his 1739 book Flora Virginica without seeking his permission. Whether or not Gronovius properly credited Clayton in the work is the subject of debate, as some felt that Gronovius greatly downplayed his contributions. However, in 1975 William T. Stearn stated that Gronovius was the true author of the work, as he had performed quite a bit of work with the material prior to the publication of Flora Virginica and that "but for Gronovius's publication Clayton's work would lack modern relevance." A second part of Flora Virginica was published in 1743 with additional information. Clayton sought to publish his own version of Flora Virginica but was unable to find a publisher before a second edition of Gronovius's book was printed in 1762. His manuscript is believed to have been lost, likely in a 1787 fire in the New Kent County clerk's office where the papers were being stored.
Clayton's work was also studied by the European botanist George Clifford and Linnaeus later named a flower in Clayton's honor, a common eastern North American wildflower, the spring beauty, Claytonia virginica. Linneus also recommended Clayton to the Swedish Royal Academy of Science, who elected him as a member on May 3, 1747. The specimens sent to Gronovius were later collected by Joseph Banks and the material is now part of the Natural History Museum in London and makes up the John Clayton Herbarium.
The site of Clayton's home is memorialized by a historical marker erected in 1951 by the Virginia State Library in Mathews County, near the community of North. It is located north of Virginia State Route 14, known as the John Clayton Memorial Highway.