Summers in the southeastern United States and in Oklahoma can be challenging for some garden crops. There is the potential in Oklahoma for cool-season vegetable crops, provided you manage the rotations with summer cover crops and select crops adapted to the cool season.
The University of Georgia has recently published a new document on Organic Cool-Season Vegetable Crop Rotations for the Southeast. While it is specifically written for Georgia conditions, many of the suggested crop rotation management ideas would work in Oklahoma. It is a short document (13 pages long), with some good links to small-scale budgets in the resource section. The publication results were developed from a Southern SARE supported grant (LS10-225).
The Kerr Center has been working with season extension since the early 1990s. We feel it has great potential for Oklahoma, but there are many considerations a grower must look at before shifting into this production model. Most importantly, what is the market for your production? What varieties are adapted and work under Oklahoma conditions?
The system requires switching your cover crop season to summer, and growing vegetables in fall and winter. While switching cover crop seasons sounds easy, you need to time your cover crop kill date to allow for enough cover crop decomposition to allow fall vegetable planting.
Fall planting is different than spring planting. As the day length shortens, plant growth slows down and eventually stops when the day length drops below ten hours per day. You need to plant your cash crop early enough to allow it to mature before it stops growing, which means planting sooner and allowing for a longer time to maturity than you would in the spring.
It can be fun to experiment with season extension in a home garden either with open planting or under low tunnels. Give it a try!