The Common fig is the most prevalent type because it develops without pollination and does not rely upon the bees to produce fruit. However, because the fruit does not produce 'true' seeds, trees have to be propogated from cuttings.
Caprifigs are different and the fruit, although non edible, produces pollen. This pollen is essential for fertilising the fruit of the other types, the Smyrna and San Pedro types. The pollen is transported from the Caprifig to the pollen-sterile types by a small wasp (termed a Blastophaga wasp) which enters the 'fruit' though a small hole at its base and lays its eggs. These small wasps are not present in New Zealand which is why we propgate figs by cuttings.
Smyrna fig varieties produce large edible fruit with true seeds. These varieties rely upon the wasp and Caprifigs for pollination and the normal fruit development. If this fertilisation process does not occur, fruit will not develop properly and will fall from the tree. Smyrna-type figs are commonly sold as dried figs.
San Pedro type figs bear two crops of fruit in one season – the first crop early in the spring is called the breba crop and is produced on the previous seasons growth, or old wood. It produces the fruit parthenogenically and therefore does not require pollination. The second crop, the main crop, fruits on the new or current growth. The fruit of the second crop is the smyrna type and requires pollination from the Caprifig. The fruit may fail to set if it has not been pollinated.
The fig has a fascinating story
It is one of the first plants cultivated by humans and was recognised as an early food source. It has a deep and exotic history and has been associated with Asian, Middle Eastern and Mediterranean climates and abundance..
An interesting aspect of the fig is that its fruit is really an inverted flower. When you cut the fig in half you can see the seeds or flower stamins. These are completely edible and form part of the flesh of the fruit. To complicate matters there are four types of fig.
The common fig, the caprifig, the smyrna, and the san pedro type.