The fig tree belongs to the plant genus Ficus, classified within the mulberry family, Moraceae. Figs have a long history, with evidence of cultivation dating back thousands of years in the Mediterranean and Western Asia. They are now distributed globally, thriving across tropical and temperate climates. The fruit is botanically unique, leading to a complex classification system that determines which types are commercially edible.
The Total Count: Understanding the Genus Ficus
The genus Ficus is one of the largest in the plant kingdom, containing between 800 and 900 distinct species worldwide. This vast number includes fruit-bearing trees, shrubs, woody vines, and hemiepiphytes, such as the famous strangler figs found in tropical rainforests. Most of these species are not cultivated for human consumption and serve primarily as ornamental plants or as a food source for wildlife.
The immense diversity within the genus means the majority of fig species produce small, often inedible fruit. The common fig, known scientifically as Ficus carica, is the primary species cultivated globally for its desirable fruit. Only this single species, along with a few closely related wild varieties, is categorized into the groups that make up the edible fig market.
The Four Main Types of Edible Figs
The edible figs that descend from Ficus carica are sorted into four classifications based on their flowering and pollination requirements.
Common Fig
The Common Fig group is the most widely grown variety for home gardeners and commercial purposes in areas lacking the necessary pollinating insect. These figs are parthenocarpic, meaning their fruit develops and ripens without the need for fertilization or viable seeds.
Smyrna Fig
The Smyrna Fig group produces the most highly valued fruit but requires a specific pollination process. The flowers inside the syconium must be fertilized by the fig wasp to stimulate the fruit to mature fully and develop its characteristic nutty flavor. If pollination does not occur, the immature fruit will shrivel and drop from the tree.
San Pedro Figs
San Pedro Figs are considered an intermediate group because they produce two distinct crops per season with different pollination needs. The first crop, known as the breba crop, develops parthenocarpically on the previous year’s wood and matures without fertilization. The second, or main crop, requires pollination to set fruit, similar to the Smyrna types.
Capri Fig
The Capri Fig is a wild fig whose fruit is typically inedible and used solely for reproductive purposes. These trees exclusively produce male flowers and short-styled female flowers, which are designed to host the fig wasp. The Capri fig acts as the essential pollen source and nursery for the insect necessary for the successful cultivation of Smyrna and San Pedro main crops.
Essential Biology: The Fig and Wasp Relationship
The classification of edible figs is directly linked to the unique biological structure of the fruit, which is a hollow, enclosed flower cluster called a syconium. This structure necessitates a specialized relationship with a pollinating insect, most commonly the fig wasp Blastophaga psenes. This mutualistic relationship is necessary for the reproduction of many fig species.
A female fig wasp enters a receptive syconium through a small opening at the tip called the ostiole, often losing her wings. Once inside the Capri fig, the wasp lays her eggs in the short-styled female flowers. While laying eggs, she inadvertently transfers pollen carried from the fig where she was born.
The eggs develop inside galls, and the males emerge first, mating with the females before leaving their galls. The wingless male wasps then chew an exit tunnel for the pregnant females. The females collect pollen from the now-mature male flowers before flying out to find a new fig. This cycle makes the cultivation of Smyrna figs impossible without the caprifig and the wasp.
In common figs, the female flowers have long styles, preventing the wasp from laying eggs, though pollination can still occur in wild varieties. Cultivated common figs bypass this process because their fruit development is triggered chemically without fertilization. This parthenocarpy allows them to be grown successfully where the fig wasp is absent.