What is an Heirloom Plant?
What are open-pollinated, heirloom, and hybrid varieties?
-An open-pollinated (OP) variety is one that breeds true from seed, meaning the seed saved from the parent plant will grow offspring with the same characteristics. OP seed is produced by allowing a natural flow of pollen between different plants of the same variety.
-Heirloom varieties are OP varieties with a long history of being cultivated and saved within a family or group. They have evolved by natural or human selection over time.
-A hybrid variety, on the other hand, does not breed true from seed; hybrid seed is produced by crossing two different parent varieties of the same species. Hybrids do not remain true in generations after the initial cross and cannot be saved from generation to generation unchanged.
Source: Seed Savers Exchange, 2012 catalog p. 5.
Widespread use of the term "heirloom" as applied to plants began in 1981 when Kent Whealy, co-founder of Seed Savers Exchange, used "heirloom" in a speech he gave in Tucson. He had asked permission to use the term from John Withee, notable bean seed collector, who had used "heirloom" on the cover of his bean catalog. John gave his permission and said he, in turn, had gotten it from Prof. J. R. Hepler at the University of New Hampshire, who first used the term "heirloom" to describe to Withee some beans he had been given by friends in the 1940s.
Benjamin Watson in Taylor's Guide to Heirloom Vegetables (1996) lists three criteria for identifying plants as "heirloom":
1. The variety must be able to reproduce itself from seed.
2. The variety must have been introduced more than 50 years ago. [The length of time since introduction for considering something "heirloom" varies among sources; some say an "heirloom" must have been introduced 100 years ago or more.]
3. The variety must have a history of its own.
Sue Stickland defines the subject of the title of her book Heirloom Vegetables (1998) as "largely those vegetables which have been preserved through the actions of a family or community, rather than maintained by commercial seed companies."
---- Bill Musser, Librarian, Seed Savers Exchange
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