I wouldn't over do it with horn worms, when I feed my guys a horn it's every couple days cause them horn worms are filling. Then on the other days Ill give them other little meals like crickets/supers/earth. Other wise you could spoil him and he'll only eat cake and no dinner

If your worms are growin too fast set cups in cooler area and it will slow them down OR buy more frogs so they can get some horn worms too