Gardening - Vegetables: Selecting & Planting
Some of these vegetable varieties and planting dates are not the same as those grown by commercial growers. Commercial growers should be sure to consult the appropriate literature for commercial varieties and planting dates.
Garden vegetables can be divided into warm-season and cool-season vegetables. Cool-season vegetables require cool soil and air temperatures if they are to germinate, grow and mature with maximum yield and quality. They are shallow-rooted and thus are susceptible to drought. They are usually grown for their leaves or roots and respond well to nitrogen sidedressings.
"SP291-O-Guide to Cool-Season Vegetables," The University of Tennessee Agricultural Extension Service, , http://trace.tennessee.edu/utk_agexgard/78