Rose Bush turning yellow
Q: Hello Tom. We have a long standing rose bush, but last year and now again the leaves are yellowing with dark spots.
I am afraid I will lose all the leaves and lose the rose bush itself.
Your thoughts are much appreciated.
A: Wet spring conditions are favorable to leaf fungi, and it sounds like you have the infamous black spot that roses get. Since this is a fungal disorder, so you'll need to do spray or dust applications to control it.
A visit to your local garden supply center should do the trick. Describe the symptoms, tell them you have a preliminary diagnosis of black spot (you might want to take in a leaf or two to show them), and ask them to
show you the various control products they have.
There are many products available that control leaf fungi, either in liquid or dust form. Dusts you simply apply by, well, dusting the foliage with the material straight out of the box.
The downside to dusts is that they wash off easily, so when you water you must be careful not to wet the leaves. You would also want to dust after a rain.
Liquids usually have a greater residual on the leaf. Some come prepared to spray right out of the bottle, others you dilute to the correct strength and apply with a hose-end sprayer.
Whatever product you choose, ALWAYS follow the label instructions for
dilution rates and application techniques. More chemical does not mean better control.
Sometimes it even reduces the effectiveness, so apply only
the correct amount per the label's directions.
You shouldn't lose the rose to this disease, but it will make the rose look pretty tired.
Dispose of fallen infected leaves regularly, and next year start with the control applications early in spring so that the disease doesn't get too far ahead of you.
Ask our Arborist a question. E-Mail us at:
Top of Page
Back to Gardening Advice