USDA Zone Hardiness Map – find out what zone you live in.
Frost Date Selector Page – find out your last average frost date in the spring and first average frost date in the fall.
Optimal Germination Temperatures by Crop – find out the best range of temperatures for germinating seeds, based on the type of seed.
National Gardening Association Plant Dictionary – look up pretty much anything garden related.
Cooperative Extension System – find your local Extension office for local gardening information.
Organic Gardening – Organic Gardening Magazine and their official website.
Garden Guides – lots of great info for gardeners.
Kids Gardening – a fun site with info for kids to learn about gardening.
Powerful Plants – Books and Seeds for kids.
Seed Companies that sell Heirloom, non-GMO seeds: