Definition of an heirloom plant: what makes a plant an heirloom?

Once one begins learning about heirloom vegetables and plants, eventually one begins to ask: "What makes a plant an heirloom species?"

Even though the heirloom plant craze is small, already marketers have crept into this budding field. The word "heirloom" is applied to seeds and strains of plants the way the words "New and improved" are plastered on laundry detergent.

So who do you trust? And what does "heirloom" even mean?

What is an heirloom? Schools of thought

The specific definition of an heirloom plant are hotly debated. Some lean toward an open, inclusive definition while others are exclusive, insisting on provenance and documentation.

One school of thought looks at the age of the specific plant. An arbitrary time period, between 50-100 years, must define the age of the plant. Some choose specific years. 1945, the end of World War 2, is a popular cut-off date. Others choose 1951, because that was the year in which hybrid plants became popular.

Others choose a more cultural approach. They contend that a plant is an heirloom only if it is treated as such: if it is nurtured, selected and handed down within a family for several generations. (This sort of heirloom certainly has the best and most interesting stories attached to it.)

Finally, many include a subtype known as commercial heirlooms. These are cultivars sold by companies that have ceased to exist. The argument is that these plants have been selected by the same forces that choose other types of heirlooms mentioned above. Indeed, most commercial plants before the age of hybrids were family heirlooms that were recognized as commercially promising by a seed company, who then offered them to the public.

Characteristics of an heirloom plant

Regardless of age, nearly universal agreement exists on these characteristics of an heirloom:

• Hybrids must be open-pollinated (pollinated by natural mechanisms, such as bees, wind, birds, etc.)
• Hybrids are not genetically modified.

So now that these questions are answered, there's nothing stopping you from getting started with your own heirloom seed planting. Don't get too hung up on the exact definition or pedigree of your tomato. Just plant it, nurture it and enjoy its fruits!