Facts About Heirloom Tomatoes
Tomatoes have always been popular with gardeners and heirloom varieties are becoming more popular every year. An heirloom is generally considered to be a variety that has been passed down, through several generations of a family because of certain characteristics. But be aware that this rise in popularity has meant nurseries have taken liberties with the use of this term for marketing purposes.
History of the Term “Heirloom”
The term "Heirloom" was apparently first used by Kent Whealy of Seed Savers Exchange, who first used "heirloom" in relation to plants in a speech he gave in Tucson in 1981. He had asked permission to use the term "heirloom" from John Withee, who had used the term on the cover of his bean catalog who had borrowed it from Prof. William Hepler at the University of New Hampshire, who first used the term "heirloom" to describe some beans that friends had given him back in the 1940s.
There are basically 4 types of heirloom tomato varieties:
Commercial Heirlooms: Open-pollinated varieties introduced before 1940, or tomato varieties more than 50 years in circulation.
Family Heirlooms: Seeds that have been passed down for several generations through a family.
Created Heirlooms: Crossing two known parents, either two heirlooms or an heirloom and a hybrid.
Mystery Heirlooms: Varieties that are a product of natural cross-pollination of other heirloom varieties.
Note: All heirloom varieties are open-pollinated but not all open-pollinated varieties are heirloom varieties.
Over the past several decades heirloom varieties have been lost due to small farms failing and large commercial farms using hybrid seeds for planting. In doing so the plants are losing their genetic diversity at an accelerating and alarming rate.
Every heirloom variety is genetically unique and has its own resistance to pests and diseases and an adaptation to specific growing conditions and climates. With the reduction in genetic diversity, food production is drastically at risk from plant epidemics and infestation by pests. This is why many countries have a Doomsday Seed Bank in case there is a disease that wipes out a variety of hybrid plant.
The following is a list of tomato terms that gardeners will routinely come across when shopping for tomato seeds and plants.
Beefsteak - A type of tomato rather than a variety considered a large, irregular shaped tomato with solid flesh.
Crack Resistant - A tomato that inherently resistant to cracking, a problem usually caused where rain falls sporadically, or where there is excessive rain.
Cultivar - The variety of a plant. However, technically there is a difference between cultivar and variety. Cultivar is considered to be a product of intentional breeding whereas Variety is the product of accidental crossing. The terms are commonly used interchangeably.
Determinate - When terminal buds set fruit and plant growth stops. Plant needs little or no staking. Harvest last only about a week to ten days.
Globe - A round shaped tomato.
Heirloom - An heirloom is generally considered to be a variety that has been passed down, through several generations of a family for favorable characteristics.
Hybrid pollination - Cross pollination accomplished by removing anthers of parent x before the release of pollen. Y parent's anther tube is opened and pollen removed to deposit on stigma of parent x.
Indeterminate - Plants that will keep growing and producing new blossoms even after fruit set. Harvest may last for several months.
Locules - Chambers within the tomato's fruit that hold the seeds within a jelly-like substance. Most fruits have 2 or more chambers and large fruited varieties have as many as 10.
Lycopersicon esculentum - The genus and species name for Tomato. All plants have a genus and species name, which are indicated in italics.
Maturity - The number of days from transplanting seedling to the first mature fruit. Early-Season varieties generally mature between 55 to 68 days; Midseason varieties- 69 to 79 days; Late season varieties from 80 days and beyond.
Oblate - A slightly flattened round shape of a tomato.
Open-pollinated - Seeds from open-pollinated varieties produce plants and fruit that are identical to their parent.
Pollination - Pollen grains released by anther and fall to the stigma, usually of the same flower.
Semi-Determinate - tomato plants are larger than determinate (bush types) but smaller than Indeterminate plants. These plants usually require staking.
Widely adapted - A variety adapted to growing well in several growing zones.