I have a Rhododendron "Nancy Edwards" in a 16 inch pot. It has always flowered magnificently year on year, and looks set with all the buds I can see about the same in the coming year. My concern is that the leaves are turning yellow and falling off, and I suspect this is down to bad drainage and I assume the plant is now pot bound. I really don't want to put it in a bigger container, as I will have a similar problem in the future; I was going to try repotting the present pot to better the drainage, but due to the size and weight this will be problematical. Is there any way that I can improve the drainage? Say by pushing a steel rod through the root ball, as there are ample drain crocks in the bottom of the pot that I put in at planting?
Rhododendron Leaves Turning Yellow
Certified GKH Gardening Expert
You can prune your rhododendron to keep it at a smaller size so that you won't need to keep repotting it. Yes, pushing a rod through the root ball will likely improve drainage, at least temporarily. You could also mix in some sand, Perlite, or other substance that improves drainage in potting soils.