Published on Organic Gardening (http://www.organicgardening.com)

Know your average last-frost date.

This date, which is specific to your location, is the average date of the last spring frost as observed over several years. Contact your county extension service for the date.

Source URL: http://www.organicgardening.com/learn-and-grow/know-your-average-last-frost-date

Links:
[1] http://www.organicgardening.com/successful-planting-know-your-frost-date-380
[2] http://www.csrees.usda.gov/Extension/