There is a science to what we plant. The success of our garden is usually specific to our growing conditions which includes soil, climate, disease, and ease of care. As a Master Gardener I know that Penn State Extension as well as other extensions around the country do research on varieties of vegetables, annuals and perennials suited for their particular state. In doing so they give the gardener information without alot of digging arouund on your own.
Penn State has free publications for the Pennsylvania gardener.
The best vegetable varieties for Pennsylvania gardeners. Link to a pdf
Information on seed packet. Link to pdf