My roses- just in one bed -have gradually leaves gone brown, and now all brown and crispy - can anyone tell me what has caused this? Not seen it before.
It looks like it could be rather advanced rose leaf hopper infestation. I have had this on all my roses this year. It starts with mottled leaves and progresses to the crispy stage if you let it. There is, I believe, little that can be done this season, other than cut all the leaves of before it becomes pronounced (though that might be a bit late for you). The RHS recommendation is to spray in spring either with insecticide or organic sprays. It is not recommended when the flowers are blooming because of detrimental effects on other insects. I intend to keep removing leaves as they show signs, and will earmark the plants for appropriate treatment next year - probably February/March time.
Thankyou Shrinking Violet, They usually get some aphids but I've not had this before. When I looked it up apparently the conditions this year have been ideal i.e. Warm and damp, and grown against a wall-which these are. Do you think I should pull all the leaves off, or leave them and spray (organically) next spring? It's such a shame, as they're flowering really well!
I am taking the leaves off, even though it makes some of the stems look rather bare. And, like blackspot leaves, I am trying not to let any lie on the ground. The leaves, especially when severely damaged, are not contributing anything to the plant, and the rose hoppers are sap-sucking critters, so best to remove leaves if possible, I think.
That looks like advance stage of sawfly larvae damage. Nothing you can do now, you probably had not noticed the small wriggly things. Best to just prune out all the damaged leaves since they will not do much now. As mentioned, clear all debris and any fallen leaves around the base. Check the stems carefully for any small cuts or openings, as that's where they may be hiding originally.
Many thanks Borderline, I'll strip the leaves off and dispose. I have a ? Dicentra (arching stems, small white hanging flowers) nearby, which has had its leaves 'shredded' and small white 'caterpillars' on, which I wondered if they were sawfly. That one has been attacked previously,but this is the first time roses have been damaged. I had been congratulating myself on managing the blackspot well this year!
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There is, I believe, little that can be done this season, other than cut all the leaves of before it becomes pronounced (though that might be a bit late for you).
The RHS recommendation is to spray in spring either with insecticide or organic sprays. It is not recommended when the flowers are blooming because of detrimental effects on other insects.
I intend to keep removing leaves as they show signs, and will earmark the plants for appropriate treatment next year - probably February/March time.
The leaves, especially when severely damaged, are not contributing anything to the plant, and the rose hoppers are sap-sucking critters, so best to remove leaves if possible, I think.