The pea (Pisum sativum) is one of humanity’s oldest cultivated crops, with evidence of its use dating back nearly 10,000 years. This long history of cultivation has resulted in remarkable diversity. When people ask how many varieties of peas exist, the answer is complex because the term “variety” is often used loosely. While a specific number is impossible to pinpoint, the range of available types extends far beyond the common frozen garden pea. Understanding the difference between a botanical species and a cultivated variety helps clarify the true extent of pea diversity.
Defining the True Pea: Species vs. Cultivar
Botanically, nearly all edible peas consumed globally belong to the single species, Pisum sativum. Exceptions, such as the Abyssinian pea (Pisum sativum var. abyssinicum), are typically considered subspecies or groups within this main species. Scientifically, there is only one “true pea” species that dominates the world’s food supply.
The different peas seen in gardens and markets are not separate species but are known as cultivars, short for “cultivated variety.” Cultivars are genetically distinct populations bred for specific traits, such as increased sweetness, disease resistance, or a shorter growing season. While the number of pea species is small, the number of distinct cultivars developed over millennia is vast and constantly shifting due to ongoing breeding programs.
The Three Primary Culinary Classifications
Modern pea cultivars are broadly categorized into three main culinary types, offering a practical way to understand their diversity. These categories are based on the structure and edibility of the pod.
The first category is the Shelling Pea, also known as the English or Garden Pea. These peas have an inedible, tough, and fibrous outer pod that must be discarded. The purpose of this type is solely to harvest the large, sweet seeds inside, which are often canned or frozen.
The second major group is the Snow Pea, sometimes called the Chinese Pea Pod. Snow peas are harvested before the seeds mature. Their defining characteristic is a flat, thin pod that is entirely edible, though a string often runs along the seam. These are primarily used in stir-fries and salads, where their slightly chewy texture is desirable.
The third type is the Snap Pea, often sold as the Sugar Snap Pea. This type is a relatively recent development, created as a cross between the shelling and snow pea types. Snap peas feature a round, thick, and crisp pod that is fully edible, offering a sweet flavor and a distinct crunch. They are harvested when the peas inside have plumped up considerably but before the pod becomes tough.
The Vast Diversity of Cultivated Varieties
The three culinary types—shelling, snow, and snap—contain thousands of individual cultivars named by breeders and seed companies. Specific cultivars like ‘Sugar Ann’ (a snap pea) or ‘Maestro’ (a shelling pea) are examples of the genetic lines that fall under the broader culinary umbrella. While only hundreds of named varieties may be commercially available in a single season, the total number of cultivars identified throughout history is estimated to be in the thousands.
This extensive genetic diversity is maintained globally by plant breeders and seed banks, which act as living repositories of genetic material. Seed banks store the seeds of heirloom varieties and wild relatives, preserving traits that might offer resistance to new diseases or adaptation to changing climates. The volume of material held in these collections, alongside constant hybridization for new traits, means the precise count of pea cultivars is always in flux.