Planting tomatoes, peppers and other summer vegetable gardens will greatly depend on the area of the country that you live in. Always on summer vegetables wait until danger of the last killing frost has pasted. Check USDA Plant Hardiness Zone Map or go to www.weather.com for your particular planting dates. Please understand these are only averages from previous data that has been compiled over several years and always keep the idea of a late spring freeze in the back of your mind when planning your garden. For example, in upstate South Carolina we are in zone 7 with an average last killing frost date of March 31, but we usually recommend that our local gardeners wait until April 15 th. One additional hint, check your local 10 day extended forecast and sometimes that will allow you to cheat just on a day or two.
Tomatoes and pepper are considered a hot weather crop. It never fails that gardeners get cabin fever and plant too early, so try to refrain from those urges and wait! If your plants do survive sometimes they just never get caught up, even with those planted as much as a month later. When planting early remember to use frost blankets and Season Starter, plastic plant guards that surround the plant that contain water. Ideally night time temperatures are 47-49 degrees with a soil temperature of 50 degrees or above.