Rose disease - Ask Extension
I'm not sure what the tiny white spots are on some of the leaves of my Gertrude Jekyll climbing rose. Aphids maybe? I used David Austin's rose food on...
Knowledgebase
Rose disease #869647
Asked May 22, 2024, 3:46 PM EDT
I'm not sure what the tiny white spots are on some of the leaves of my Gertrude Jekyll climbing rose. Aphids maybe? I used David Austin's rose food on May 1, but have not used any other systemic treatment. I've tried Neem oil in the past - and I'm not a fan of it. Can you tell me what this infestation/ disease might be and how I should treat it?
Dakota County Minnesota
Expert Response
It could be aphids but more likely spider mites. Stripling like this is common with spider mites. The treatment is the same. Start with a strong water spray. Chemicals are the second line of defense. See the website for details.
1. https://hortsense.cahnrs.wsu.edu/fact-sheet/rose-spider-mites/
2. https://extension.umn.edu/yard-and-garden-insects/spider-mites
1. https://hortsense.cahnrs.wsu.edu/fact-sheet/rose-spider-mites/
2. https://extension.umn.edu/yard-and-garden-insects/spider-mites
I don't think you're correct. Based on one of the articles you pointed to, I took a magnifying glass and looked on the underneath side of the leaf to see if I could see spider mites. There was no webbing. Also the photos showing spider mite damage from your article did not look anything like the white spots on my rose leaves. Upon further examination, I found tiny greenish worms on the underneath side of the leaf. I think the roses have rose slugs.
Yes, the closeup of the underside of the leaf and insect picture which would be better as a closeup are spot on. You could have both but the sawflies/slugs are a good discovery. So now you know what to treat. Treatment is the same.
https://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advice-tips-resources/insects-pests-and-problems/insects/sawflies/rose-and-pear-slugs-sawflies#:~:text=Use%20an%20Insecticide.&text=Horticultural%20oil%2C%20insecticidal%20soaps%2C%20neem,before%20infestations%20reach%20critical%20levels
.
https://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advice-tips-resources/insects-pests-and-problems/insects/sawflies/rose-and-pear-slugs-sawflies#:~:text=Use%20an%20Insecticide.&text=Horticultural%20oil%2C%20insecticidal%20soaps%2C%20neem,before%20infestations%20reach%20critical%20levels
.
