An Heirloom plant, heirloom variety, or (especially in the UK) heirloom vegetable is a cultivar that was commonly grown during earlier periods in human history, but which is not used in modern large-scale agriculture.

Many heirloom vegetables have kept their traits through open pollination, while fruit varieties such as apples have been propagated over the centuries through grafts and cuttings.

The trend of growing heirloom plants in gardens has been growing in popularity in the United States and Europe over the last decade. (2000 - 2009)

Origin - Before the industrialization of agriculture,
a much wider variety of plant foods was grown for human consumption.

In modern agriculture in the industrialized world, most food crops are now grown in large, monocultural plots. In order to maximize consistency, few varieties of each type of crop are grown. These varieties are often selected for their productivity, their ability to withstand mechanical picking and cross-country shipping, and their tolerance to drought, frost, or pesticides.

Heirloom gardening is a reaction against this trend.

Typically, heirlooms have adapted over time to whatever climate and soil they have grown in. Due to their genetics, they are often resistant to local pests, diseases, and extremes of weather.

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In popular usage, an heirloom is something, that has been passed down for generations through family members.

English legal history

The term originated with the historical principle of an heirloom in English law,
a chattel which by immemorial usage was regarded as annexed by inheritance to a family estate.
Loom originally meant a tool. Such genuine heirlooms were almost unknown by the beginning of the twentieth century.

Any owner of a genuine heirloom could dispose of it during his lifetime, but he could not bequeath it by will away from the estate. If he died intestate it went to his heir-at-law, and if he devised the estate it went to the devisee.

The word subsequently acquired a secondary meaning, applied to furniture, pictures, etc., vested in trustees to hold on trust for the person for the time being entitled to the possession of a settled house. Such things were more properly called settled chattels. As of 1 January 1997, no further settled land can be created and the remaining pre-existing settlements have a declining importance in English law.

An heirloom in the strict sense was made by family custom, not by settlement.

A settled chattel could be sold under the direction of the court, and the money arising under such sale is capital money The court would only sanction such a sale if it could be shown that it was to the benefit of all parties concerned and if the article proposed to be sold was of unique or historical character. The court had regard to the intention of the settlor and the wishes of the remainder men.

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Heirloom, mostly plants, animals too, can be an "ARK" or Presidia food also.