Well I can't send you exactly to where you need to find the info, but the info is certainly out there if you google, or otherwise search, for average last (spring) frost date and average first (fall) frost with your city, county/state, or zip code. There is also the (brand new) USDA Hardiness Zone maps which may very well link you to the dates you need. I have family on the Gulf Coast of Mississippi and I believe they are zone 8a/b with approximate average date of last spring frost March 20-April 1 and approx date for the first fall frost about Nov 15-30. Don't take this as gospel but it's a fair estimation.

Hi, Dana
I live in Mississippi, also in Zone 8A (under the new zone map). My last frost date is typically between the last week of March and the second week of April. The probability of frost goes down the later the date is.

So, when do you plant? I can tell you my system. In late March, I start watching the Weather Channel religiously. I watch for night time temperature lows to be at or above 55 degrees. When they are projecting a week to ten days ahead with EVERY night low at or above, 55, I get out my soil thermometer, which is just a meat thermometer with a metal probe and the thermometer part on top. When the temperature of my soil is 60 degrees, I plant beans and tomatoes. I usually wait a week or two longer for soil temps to be at or above 65 to plant cowpeas and cucumbers. Typically my soil temps will be adequate right from the start since I garden in raised beds. But if not, I wait. Tomatoes can be stunted and bean seed will rot if the soil temperature is too cold.

You need to understand that no system is foolproof. There is always the chance of a freaky late freeze coming along and spoiling everything. But that is unusual and when it happens, you just replant.

Here is a link that might be useful: Find your last frost date here

Thanks Donna! That's a good system to use and I may use it myself :) My LFD is also the end of March. I'm getting so antsy to start filling up my garden. Still a good 6 weeks to go. My tomato plants just sprouted yesterday and my broccoli a few days ago.

Oh, good, Dana! I know just how you feel. I am going to be starting lots of seeds this next week myself. I also took advantage of this warm weather and last week I got out and double dug my tomato beds for this year. It felt so good to be out there working!

If you have not added compost, chopped leaves, manure, or some other kind of organic material to your beds yet, now is a great time to do it. Even if it is still not all the way composted, you can stir it into your soil and it will work absolute miracles on the fertiliy and texture of your soil by the time planting time comes. Once I work mine, I immediately cover the entire bed with a thick layer of mulch. That keeps weeds from sprouting in the beds and stops rain from compacting the soil. When planting time comes all I have to do is push the mulch back and plant my transplants with a trowel.