ginger
薑 refers specifically to ginger, the plant or its root.
薑 combines 艹 (grass/plant) with 畺, which likely contributes the sound and relates to the plant's strong, boundary-like taste. The character is the traditional form; the modern Japanese simplified form is 姜.
The grass top 艹 signals a plant, and the bottom 畺 looks like a patch of land with rows. Imagine ginger growing in neat rows in a field.
For キョウ, picture a strong ginger root shaped like the kana きょう (kyo-u). The root's shape spells out キョウ.