I have a compact area with about thirty shade tolerant shrubs (chosen for that reason) including pieris, mountain laurel, rhododendron, camellia, fothergilla, azalea, and heavenly bamboo. They were planted last March in good soil, and they have (mostly) done great over their first year. Is there any fertilizer that will benefit all of them? When should it be applied, and how? I was thinking of Plant Tone and/or Miracle Grow.