did you dry it at all before putting it in the jar? id set it in a brown paper bag with the opening slightly open and let it dry untill the stem snaps cleanly and then you could cure it if you like by putting it back in a jar for a week or so, just make sure you open the jar every day or two to let out the nasty chemicals that are released when the chlorophyll breaks down. the longer its in a dry jar with occasional fresh air, the more chlorophyll breaks down and the better it will taste.