The plant is about 9 years old and has always been very healthy. This year it has these rust looking spots on leaves, the leaves themselves are a much paler green than usual with the veining still the dark green. Any advice is much appreciated. Katy
What is wrong with this oakleaf Hydrangea?
What kind of weather have you had?We had cold and wet weather the two weeks before Mother's Day and some cool(down right cold)for almost a week in June that caused problems for my area.Mainly tomatoes,causing leaf spot and curly top wilt.
The light leaves w/darker veins could be an iron deficancey(sp?).
P
Perhaps that is it, we have had an unusual amount of rain this year but the temperature has been pretty normal. How does one get iron in the soil?
Thanks for your response - Katy
Katy,
It looks to me like it might be getting it's fall leaf color early. From the way the pink is spreading out on the leaves. It might have been under some stress, and is going into fall color early. The stress might account for the lighter green of the leaves, also.
Personally I don't think it looks like anything serious, the new leaves look good, and the flowers look like they were fine.
However, there are many more knowledgeable than me.
May I suggest you post this on the tree and shrub forum, and you will get a lot of very savvy and helpful people there to assist.
Polly
Hello, Polly. It looks like a cercospora fungal infection to me. The product(s) that can help must contain one of the following ingredients in the label: azoxystrobin, chlorothalonil, mancozeb (sold as Mancozeb, Manzate, etc), myclobutanil (sold as Immunox, etc) or thiophanate-methyl.
You will find some of these in nurseries that sell a lot of roses. They should have products with mancozeb (because it is good for blackpot). Immunox would also work but is slightly less available over here for some reason.
If you cannot get them locally then check Rosemania's Website. They have good prices and do not charge for shipping. Go to www.rosemania.com, click the button that says Downloads and click the link that says Rosemania 2005 Product Catalog for a list of fungicies and other stuff that they sell.
Other cultural controls for cercospora deal with such things as improving the airflow around the plant, making sure that watering does not wet the leaves too much, replacing the mulch with new mulch and disposing of infected leaves in the trash.
Luis