ID leaf spot on Rhodo

15 years ago

Hi, could use some reassurance please. 36" Rhodo 'Rocky White' planted last spring, from Lowes. Mounded for good drainage, overwinter with a mulch of pine needles, northeastern exposure but protected from winter winds. Pretty mild winter in these parts. It at first reminded me of Rust, but I didn't see any yellow spores, I think it could be chemical damage possibility from contractors who just do there job without regards for surrounding. They were spraying with a sealer type thing for brick chimney and grill protection. {{gwi:387112}}{{gwi:387113}}{{gwi:387115}}

I am sorry the pictures are so bad. If they don't work, I will try again.

Thank you in advance.

Ally

Comments (2)

jean001
15 years ago
The upper right picture is drought stress. Most likely the rootball ran short of water. And may still be dry.

Further, the roots haven't had time to extend into the surrounding soil.

So you'll need to water -- very slowly -- directly on top of the rootball for a while. And, if you get lots of hot sunny days, you might want to rig temporary shade.
rhodyman
15 years ago
The plant looks very healthy except for the affected leaves. I would not worry about the plant at all.

Wind and cold damage is indicated when the edges of the leaves become distorted and turn brown. This occurs frequently in plants that may be in a colder climate than recommended or in a location with severe exposure. Provide protection from winter winds and winter sun. Note, boron poisoning or fertilizer burn will create the same symptoms except uniformly over the plant rather than just on areas exposed to the sun and wind.

Leaf spotting can also be caused by chemical injury, such as drift from cleaners, paints, or chemicals used to kill moss on roofs as shown in the photo on the right. Sometimes the results of such injury may not show up for weeks or months. It is usually more random and not just on the edges and tips of the leaves.

Here is a link that might be useful: How to grow rhododendrons and azaleas.