Good luck Paul. Have you tested the ph of that bed? As I understand it sulfur treatment can take a while to take affect so the Miracid should help a lot. I supplemented with Espoma Holly-tone only because I had it. Given the numbers, 4-3-4, it's probably not very cost effective for hungry JI. Is sphagnum peat readily available to you? That might help as well as an acidic soil amendment.