I make it about 136 years since the first garden was planted by a white man in the Jamestown area. The planting was done by the soldiers at Fort Seward and was probably somewhere near the present site of the Anne Carlsen Center, according to the old post records.
Army regulations required that each post have a garden. These gardens were mostly cabbage, onions and squash. Crops that would keep in a root cellar into the winter.
The reason the army required gardens was the fresh produce was the best way to prevent scurvy among the soldiers who lived on a fairly constant diet of salt pork, beef and beans.
I assume the efforts of most modern gardeners are not a mater of life or death.
Some post commanders were lax about their garden mission. During one winter in the 1870s the mortality rate for soldiers at Fort Rice, near present day Fort Yates, was 10 percent due to scurvy.
It would seem that unless you had General Custer as a commander you were more likely to die of disease than a bullet if you were in the army on the frontier.