Answer: Essentially, an heirloom plant would be anything that has been passed along from gardener to gardener as an old favorite. Some people use the term in the sense of meaning historic, but that too is open to interpretation! Within some broad guidelines, then, there are some catalogs that specialize. Burpee ( http://www.burpee.com or 800-888-1447 to order a catalog) publishes a special heirlooms catalog including both vegetables and flowers and Select Seeds ( http://www.selectseeds.com/ ) offers exclusively what it deems heirlooms with the emphasis on flowers.
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