Certified GKH Gardening Expert
It will not hurt it at all! If it has been wet in your area, you may want to dab the cut area of the plant with peroxide to keep it from getting an infection. Otherwise it will not hurt them.
This article will give you more information on the plant: https://www.gardeningknowhow.com/ornamental/shrubs/rhododendron/rhododendron-care.htm