Mahoutsukai no Saku Niwa

The Blanket Kingdom and the Laculus Empire are rival nations. Toto, the princess of the Blanket Kingdom, and Rayona, the princess of the Laculus Empire, both become apprentices to the great wizard Ozuno. But after three years as his apprentice, all he's taught them is the magic to produce a little salt water and a little wind... (Source: Hakusensha, translated)