Punica granatum ‘Nana’ in bloom at The Cloisters. Photograph by Barbara Bell.
There are two forms of Punica granatum: one is a large shrub or small tree; the other is a dwarf form suitable for growing in pots. The dwarf form is known as P. granatum ‘Nana.’ The standard botanical epithets applied to forms smaller than the species type are derived from nanus, the Latin for “dwarf.” Since the grammatical gender of the genus Punica is feminine, the feminine form of the adjective is used to modify it.
There is no evidence that the dwarf form of the species was known and grown in the Middle Ages. According to Alice M. Coats, P. granatum ‘Nana’ was introduced into England from the Himalayas (Garden Shrubs and Their Histories, 1965), and was cultivated in the Chelsea Physic Garden by the eighteenth century. Since the dwarf pomegranate is so well suited to container culture, and is so much more manageable, we include both the dwarf and standard forms in our plant collection. This allows us to cultivate more specimens of a very beautiful and significant species that is one of our signature plants, displayed in all three cloister gardens.
The Royal Horticultural Society’s Index of Garden Plants (1994) lists only one species in the genus Punica, and P. granatum has long been regarded as the sole species in the Punicaceae, although some taxonomists have now placed Punica in another botanical family, the Lythraceae.