While the yellow foliage of my John Cabot climbing rose contrasts nicely with the blue wall behind, it's not supposed to be yellow!
I actually have quite a few plants in one area with leaves that are turning yellow. I suspect the problem is the roots left over from a giant willow tree we had taken out a couple of years ago. The rotting wood in the ground is using a lot of nitrogen, meaning less available for the plants.
Another common cause of yellow leaves with green veins is iron chlorosis, caused by a lack of available iron in highly alkaline soil. If you see this, you can get chelated iron, which is mixed with water and applied either directly to foliage or watered into the soil. Acidifying fertilizers also help, such as blood meal and fertilizers with sulphur. Cut off a few leaves and take them to a good garden centre and ask for advice, or consider getting your soil tested.
Comments