They are usually interpreted as a symbol of physical or spiritual malaise that will hit us, or will manifest from within, like an infection. If when you dream of them, is not their season, it can also be interpreted as a secret passion that we cannot confess.
Dream dictionary: Eggplants dream meanings
In season, an eggplant in a dream means earnings with little effort, while seeing an eggplant out of season in a dream denotes negativity and disliked. Eating an eggplant in a dream means falling prices. An eggplant in a dream also represents the element of arrogance, self adulation, perfidy, cheat- ing others, and a man with many faces. As for fishermen, seeing eggplants in a dream means a good catch, joy and success.