Last Expected Frost Dates by Zone
Zone 1: June1 - June 30
Zone 2: May 1 - May 31
Zone 3: May 1 - May31
Zone 4: ;May 1 - May31
Zone 5: March 30 - April30
Zone 6: March 30 - April30
Zone 7: March 30 - April30
Zone 8: February 28 - March 30
Zone 9: January 30 - February 28
Zone 10: January 1 - January 31
Zone 11: Frost Free Year Round
Here is a link to the USDA's Hardiness Zone Map. http://planthardiness.ars.usda.gov/PHZMWeb/
Use these dates to help choose the best plants for your area. Some perennials require specific temperatures so make sure your zone is appropriate before investing in your plants.