I have a beautiful old Hydrangea. It usually has beautiful blue flowers. (I dry many of them. ) The last 2 years the flowers only open on the outer edges and the center buds don't open. We water and have mulch around the plant. We prune only the dead stems when necessary. We've done everything we know to do but nothing is working. Please help if you can. Thank you.
My Hydrangea Flowers Won’t Fully Open
Certified GKH Gardening Expert
It is likely lacking a good phosphorus/nitrogen balance in the soil. Too much nitrogen or too little phosphorus will cause it to fail to bloom or reduce its flowering potential. This article will have some other suggestions as well: