Search for other topics in Food-Skills-for-Self-Sufficiency.com:
In the chart below are the average frost dates (last spring and first fall) by USDA Plant Hardiness Zone. Use this information along with this USDA zone map to determine when to plant specific vegetables in your garden. Remember these are AVERAGE dates, and are not 100% reliable. Some years frost temperatures stay later in the spring and come earlier in the fall. My personal experience is that these dates are accurate 95% of the time for zone six.
If you live in the northern portion of a zone, or the "a" sub-zone, you
should figure that your last spring frost will occur later in the date
range provided above and that your first fall frost will occur earlier
in the date range. If you are in the southern portion, or the "b" sub
zone, then the opposite is true.