Pomona is the goddess of poma — tree fruit, as distinct from grain, from vines and from garden vegetables. Her instrument is not a bow or a torch but a pruning knife, and Ovid is explicit that she has no interest in woods or rivers, only in the cultivated orchard: grafting, watering, cutting back. She belongs to a category Rome had and Greece largely did not, the deity of a specific agricultural technique.
She is also one of the strongest single arguments that Roman religion is not derived Greek material. There is no Greek Pomona. There is nothing to translate her from.
The evidence for how old she is
Her cult record is nearly empty. Search the surviving painted and inscribed calendars for her day and there is none; look for her in the historians and she is barely there; no building in Rome carried her name. And yet she had a flamen — the flamen Pomonalis, listed by the antiquarian Festus as the last and least of the twelve minor flamens.
That combination is the informative part. A flamen is a mark of great antiquity, since the college of flamens was fixed early and never extended to fashionable later gods; Rome had priests for Pomona and Falacer and Furrina while having none for Venus or Fortuna. So the correct reading is not that Pomona was unimportant, but that she was important very early, in a rural Latium that left no texts, and was already a residue by the time anyone in Rome was writing.
A sacred grove associated with her, the Pomonal, is placed by ancient sources on the road towards Ostia, in the territory south of Rome — orchard country.
Vertumnus in disguise
Her one story is told at length in the fourteenth book of Ovid's Metamorphoses, and Ovid takes the trouble to set it in Latium under one of the Alban kings, in the stretch of the poem where he is deliberately working with Italian rather than Greek material.
Vertumnus, a god of change and of the turning year — Etruscan in origin, with a bronze statue in the Vicus Tuscus in Rome that Propertius makes the speaker of an entire poem — is in love with her. She has walled herself into her orchard and admits no suitors. He comes to her repeatedly in disguise: as a reaper with a basket of ears, a herdsman, a ploughman, a vine-dresser, a soldier, a fisherman. Finally he arrives as an old woman, admires the fruit, kisses her in a manner Ovid notes no real old woman would have managed, and argues the case for marriage — pointing to an elm with a vine trained on it and observing that neither would be worth much alone.
He then tells her a cautionary tale about a girl who spurned a lover until he hanged himself at her door, and whom Venus turned to stone as she watched the funeral pass. When Pomona is still unmoved, he drops the disguise and stands there as himself, young, and she is convinced by the sight.
Whether Ovid found this story or made it is genuinely unclear. The two deities are independently attested and their pairing is plausible for Latium; the elaborate disguise sequence and the inset tale are exactly what Ovid does elsewhere with material he is embroidering. It should be read as a Roman poet's version of a Latin theme, not as a transcript of Italic myth.
Grafting as a religious matter
The technical background is real and matters. Roman fruit-growing was sophisticated — Pliny the Elder devotes long stretches of the Natural History to varieties of apple, pear, plum and fig, and to grafting methods; Columella and Varro give practical instruction. An orchard is a long-term investment made by someone who may not live to eat from it, and grafting is the deliberate creation of a tree that could not exist without human intervention.
A goddess presiding over that work is presiding over patience and technique rather than fertility in the raw. Divide the agricultural year finely enough and you get a deity per operation, which is exactly what the priests of Ceres did for the plough; the orchard version of that habit is Pomona. It is among the least Greek things about Roman religion.
Her name on the map
Pomona, California was named in 1875 in a competition, by a nurseryman, for a district planted with citrus and vines — and gave its name in turn to Pomona College. The science of fruit cultivation is pomology, and the fruit-growers' societies of the nineteenth century used her name constantly. Latin pomum runs on into French pomme, into pomegranate (pomum granatum, the seeded fruit), and into the pommel of a saddle or sword, named for its apple shape.
Arcimboldo's celebrated portrait of the Emperor Rudolf II as Vertumnus, a face composed entirely of fruit and vegetables, keeps her suitor visible in art history. And J. K. Rowling gave Hogwarts' herbology teacher the name Pomona Sprout, which is a joke that works only if you know the Latin.
Questions about Pomona
Was she worshipped alongside Vertumnus in cult?
There is no evidence that she was. Vertumnus has a genuine Roman presence — his statue in the Vicus Tuscus, a temple on the Aventine, and an Etruscan background as Voltumna, the god at whose sanctuary the Etruscan league met. Pomona has the flamen and almost nothing else. Their pairing is literary, and the fact that a poet found it natural does not make it a cult reality.
Is she connected to autumn festivals?
Not in any documented Roman way, though the association is intuitive and modern writers make it constantly. The Roman harvest festivals in the calendar belong to other powers — storage to Consus, the vintage to Jupiter at the Vinalia. Claims that Pomona lies behind Halloween's apples, which appear regularly in popular writing, rest on a Victorian antiquarian habit of attaching Roman names to British folk custom and have no ancient support.
Do any images of her survive?
Statues and reliefs of a young woman with fruit gathered in her lap or a fold of her dress are conventionally identified as Pomona, and Renaissance and Baroque sculptors produced many more. As with most minor Roman deities, an identification without an inscription is a label of convenience: a woman with fruit could equally be a personification of Autumn, of Abundance or of a province.
Why do so many Roman deities have no myths at all?
Because myth-telling and cult were separate activities in Rome, and the second came first. A Roman deity is defined by what is done for it and when, not by what happened to it. Pomona, Terminus and dozens of others have precise jurisdictions, priests or rites and no narratives whatever, and the ones that do have stories usually acquired them from Greek literature or from Ovid. The absence of a myth is not a gap in the record; it is the record.