Can anybody help me determine what’s going on with some of my roses that look like this?
It appears to be “Rose Slugs”, Sawfly larvae. Small, green worms on the under sides of the foliage eating the green tissue, leaving the surface cuticle or “skin”. There are a number of organic and inorganic remedies easily found on a Google search for you to determine which is the most acceptable to your gardening philosophy.
1 Like
Agree with sawfly larvae diagnosis. Bonide has a good systemic insecticide product that I have used in the past and it seems to work.
1 Like
Thank you. I will have another question, but I am away from our home and want to send another pic. Thanks again
You’re welcome. Should you wish to explore predatory insects for them, there is this recent thread here in this Forum. Which beneficial insects work on sawfly larvae?
As promised here is another picture same Rose. Just want to see if this is also the aftermath of the same sawfly larvae?
No, that appears to be powdery mildew on the foliage surface. It can also cause the foliage to curl as your photo shows. It’s a bit difficult to see due to the curl of the leaf, but that’s what it appears to be.
1 Like
Different treatment?
Yes, different treatment. The sawfly larvae (rose slugs) are insects which eat the under sides of the foliage. Powdery mildew is a fungal infection which may clear up if the weather warms and dries to the point it no longer supports the spores germination. Or, perhaps increasing the water to the plant may help it clear up. I’d long read in rose books how water stressing a rose can force even a mildew resistant type to mildew. I didn’t believe it until I did it. Water stressing a rose can also force it to rust. I would first try increasing the water to the plant and watch the new growth to see if it stops mildewing. If it does not, then you can decide which of the many treatments you consider appropriate for your garden. There are “organic” and “less toxic” treatments as well as the “nuclear options” of more toxic treatments. What you decide to use is your choice.
2 Likes
Welcome to the forum. Powdery mildew, a fungus, I recommend Myclobutanil to treat it, if you are not adverse to chemicals. Horticultural oil can help too.