When I add fertilizers (which isn't very often) it's usually just the standard tomato stuff. 15-15-30 or something like that. But for the most part I usually just stick to Alaskan fish fertilizer and this other stuff I got that has bat and rabbit poop, seaweed and a few other natural things in it. Other than that I just try to make sure the soil is good from the beginning so I do add a 30% mixture of worm castings to potting mix.