Over the winter I had created a mini sensory garden for my infant son. It had red leaved lettuce, snow peas, thyme and nasturtiums. He loves playing in the dirt, feeling the plants and pulling the lettuce to pieces. I'm now looking to change it up for the spring and summer. It's in a pot about 3 ft in diameter, in partial sun, and the plants need to be 100% non-toxic though of course he's thoroughly supervised when he's out playing (he's 11 months old now). Does anybody have any suggestions of plants that could work? Thanks very much.