Ancient runic use was for writing and charm rather than a fixed oracle. In modern rune divination Jera is read for cycles, harvest, fruition and the reward that comes at the right season after patient work. These associations derive from the twentieth-century reconstructionist and esoteric tradition rather than from the historical record, and are presented as a symbolic system, without any claim of foretelling.
Jera's consistent attestation across all three surviving rune poems as harvest and the cyclical turning of the year gives the modern divinatory keyword sense of cycles, harvest and the fruit of long effort a comparatively direct basis in the older material, unlike runes whose ancient meaning is split or obscure. It is worth noting even so that no rune poem describes Jera being cast or drawn to answer a question; the ancient material describes what the year itself means, not how to divine one's own fortune by the rune's name.
The Armanen-descended rune-magic tradition transmitted into English chiefly through Thorsson's work also treats Jera as usable actively rather than only read passively: chanted aloud as galdr, or carved into wood, metal or a bind-rune combining several staves, for an intended practical effect. No source earlier than the twentieth century attests any such active magical use of this specific rune, and the practice should be understood as a modern reconstruction built on the reconstructed name and the rune poems rather than as a recovered ancient technique.