My hydrangeas have been yellowing for a couple of years. Up until now I‘ve treated them with an iron supplement. Note – Yellow leaves are a very different issue than ASTER YELLOWS.

After doing some research, I’m ready to work on some probable causes:

– lower the pH

– correct a drainage problem

– As always, I should be doing a soil test before doing anything else!

Here are three excellent articles on identifying and dealing with chlorosis:

Missouri Botanical Garden – Iron Chlorosis

Utah State University – what is Iron Chlorosis and What Causes it?

Government of Canada Agriculture – Iron Chlorosis


Hydrangea with yellowing leaves and green veins. Very typical of chlorosis.

Asiatic lilies in same bed are now showing symptoms

A product I’ve been using to treat symptoms