What's an heirloom?

While "heirlooms" are family keepsakes that you can't throw away, there isn't a universally accepted definition of "heirloom plants." The broadest definition mandates that a plant variety meet three qualifications:

1. Able to reproduce itself from seed.
Most heirlooms are open-pollinated, meaning that they grow true to type from seed. On the other hand, seeds from hybrids are usually sterile or grow a plant true to one of hybrid's parent forms. The exceptions to the true-to-type rule are those plants that gardeners grow from cuttings or roots, such as potatoes, asparagus, onions, rhubarb, and garlic.

2. Must have been introduced at least 50 years ago.
Fifty years is just an arbitrary number--some heirloom lovers go by a 100-year rule.

3. Must have a history.
This is my favorite part of heirlooms. A variety of pole beans that may have been carried to America on the Mayflower, or cucumbers introduced in Philidelphia in 1928, or green dent corn planted by a pre-Columbian civilization in Mexico--these are heirloom plants. Plants that have a history.

Myself, I'm planting Bull Nose bell peppers this year. Thomas Jefferson planted them at Monticello.

 I need to give credit to Benjamin Watson, who wrote Taylor's Guide to Heirloom Vegetables, for most of the information in this post. The book is great and you should either buy it or check it out of your local public library and start racking up late fines.