i read that you should only use the unsulphered,and thats wat i did and never looked back,i never had any ill efects on i plants,and yes sulpher in the levels present in that type of molases would hurt your plant,hope iman helped im very high rite now and having a hard time vocalizing or typeitizing my method .,.,.just get the unsulphered black strap molases and youl be happy and irie