Jera is the Rune of the harvest, but it is also the rune of the hard work that goes into the harvest and the changing of the seasons. The Nine and Eight of Pentacles represent the practical parts of this rune, while The World and The Wheel of Fortune represent the natural cycles inherent in Jera.
While for most people today, agriculture is simply a metaphor for hard work that follows cycles of productivity, during the time the Tarot was created, and even more so the Runes, the vast majority of the population lived and died based on their agricultural success. It is only due to modern irrigation (Laguz, ᛚ) and modern tools (Ehwaz, ᛖ), that our fields are so fertile (Inguz, ᛜ). As a result, most of us have never set foot on a farm in our lives. We don’t have to: those crops are put on a truck (Raidho, ᚱ) and brought to our local supermarket (Gebo, ᚷ).
In Wicca, this Rune represents the Wheel of the Year. Many Heathens and Asatruar reject this interpretation of the rune along with all influence from the Western Mystery Tradition. The part that everyone agrees on is that Jera is associated with the changing of the seasons and the knowledge of which crops must be planted and harvested at particular times.
Divination:
Jera usually represents a single discrete project that the querent is working on. It is usually something that they have nearly finished and are about to receive their reward. I tend to interpret this rune in the same way that I interpret the Eight of Pentacles.
In some readings, though, it has more of a Wheel of Fortune feel to it. Sometimes, this is talking about the things that go around in circles, and that only get better if you make them better. I tell the querent that this is a rune recommending that they put in the work to make that change.
Use in Magick:
Jera belongs in any garden or field of crops. It is the rune of the work to make those crops grow, and the rune of the harvest at the end of the season.
Carve Jera into the bone of a fish and bury it with the seeds you plant. This is a merging of European magick, the runes, and North American magick: the burying of a fish with your crops to make the soil richer and stronger.