The answer to your question depends on what you mean by "large-scale agriculture." If you are asking did the Native Americans in the Great Plains practice agriculture in some massive or industrial scale then your answer would be no.

However, Native Americans in the region certainly practiced agriculture for hundreds of years and this was an extremely important part of their diet, settlement, daily life, and ritual. Today, we might consider the kind of agriculture practiced to be more like modern gardening, considering food was grown at a small scale and to be eaten, not sold in a market. Still agriculture was hugely important, at whatever scale, and discounting the agriculture of Native Americans in the Great Plains would be a huge mistake.

An early anthropologist named Gilbert L. Wilson wrote several books on the culture and agricultural practices of Great Plains Native Americans, especially the Hidatsa. His P.h.D. dissertation was essentially comprised of interviews with Buffalo Bird Women, an elderly Hidatsa woman who had extensive knowledge of the history of Hidatsa agriculture. The book that he later published, Buffalo Bird Woman's Garden (1917), is a classic and clearly demonstrates the importance of agriculture in the Great Plains region for Native Americans. I would definitely recommend reading it if you have more specific questions or want to understand the details of what agriculture looked like in the region.