[foxhop]

There are two factors for growing food that I learned the hard way, "when to plant" and "plant temperature tolerances"

For when to plant, I use this web site, if my desired plant isn't on the chart, I make a best guess based on related plants:

http://www.almanac.com/gardening/planting-dates

As for temperature tolerances, googling the "hardiness of a tomato" is a great stepping stone.