Answer: Summersweet or Clethra usually requires little or no pruning, it should leaf out along the existing stems and twigs.
Ideally, you would run some basic soil tests and fertilize -- if needed -- specifically on the basis of the results. However, if the shrubs are planted in a lawn area and the lawn is fertilized, then that should be enough for the shrubs as well. If located in a planting bed, a complete general purpose fertilizer such as a granular 10-10-10 can be applied in early spring according to the label instructions, and/or you could apply some compost to the root zone in spring or late fall.
The water soluble types of general purpose fertilizer are also fine instead of the granular but again, read and follow the label instructions. It is actually better not to fertilize than to overfertilize.
Enjoy your summersweet!
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