An heirloom variety or heirloom vegetable is an old cultivar that has been saved across generations or across several decadesis by gardeners and farmers. The varieties may have been commonly grown during earlier periods in human history, but are not used in modern large-scale agriculture. Some associations are preserving seeds of the older cultivars in seed banks. In the European Union, it is illegal to sell seeds of cultivars that are not listed as approved for sale. All heirloom varieties are usually open-pollinated.