What are red beans

Red bean: a southern plant, also called "acacia". The ancients often used it as a symbol of love or lovesickness.

Tang Wang Wei "Love" : "Red bean raw south, spring to send a few branches; May you gather many, it is the most loved."

Tang Wentingyun "new add sound Yangliuzhi words" two: "Linglong dice an red bean, bone acacia know?"