Published on Organic Gardening (http://www.organicgardening.com)
Figure out what soil temperatures your favorite vegetables prefer and what weather they can tolerate. Go here for the ideal temperature ranges of most vegetables. Use your last-frost date to establish planting dates. Just be sure that the soil is warm and dry enough before planting.
Links:
[1] http://www.organicgardening.com/successful-planting-know-your-crops-380
[2] http://www.organicgardening.com/learn-and-grow/seed-starting-glance-0