I have to severely cut back a 30-year-old, 16' high photinia after a tree fell and broke the trunks. I have cut four trunks (on south side) to 4' high and left four intact trunks. 1. How can I best spur the growth on the cut trunks? 2. Would putting some growth hormone on the cut trunks help? 3. Any special fertilizer for regrowth?
Photinia Pruning and Regrowth
Certified GKH Gardening Expert
Your best fertilizer will be one that is higher in nitrogen. Nitrogen spurs foliage growth and will encourage it to grow faster.
Since the plant was badly damaged, a fertilizer with essential micro-nutrients would be helpful as well.
The cut branches will probably grow back quickly on their own and rather thickly. Keep an eye on this as you may need to thin out new growth on those branches in order to have a healthy plant.