Comfrey has many benefits. Get the sterile one, Symphytum Officinale (common comfrey), which is propagated by the root, not seeds. The tap root goes deep into the soil to bring up the nutrients for nearby plants. Plant it under your fruit trees with a wild flower mix that attracts beneficial insects.
You can also soak the leaves in water for a health tonic for your plants.
The plants below are going in a client's orchard this week.