Does my rosebush have a disease?? If so what kind??

Question

I have a small white rosebush planted infront of my house that has recently dropped almost all of it's lower leaves. When you look at the fallen leaves they are green but marbled with black. Not like dry black spots, just actual black coloring marbled through the leaves. I have had trouble with aphids as well as japanese beetles this year causing me to use 2 different kinds of bug killer on them, Bayer for Roses and sevendust, could this have caused it? Any ideas or rememedies would be greatly appreciated!!!!!!! P.S- all my other rosebushes are fine.

Answer 1

Your bush has a disease called 'blackspot'. I am not kidding, this what it is called. It is caused by a fungus that colonises the leaves and affects them to the point where they drop off. some roses are more susceptible than others. It can be quite difficult to treat, use a fungicide containing copper. You should collect all the fallen leaves because they contain the spores for next years infestation.

Here is a site to confirm.

http://images.google.co.uk/imgres?imgurl...

Answer 2

The bush is probably suffering from chlorosis,inability to manufacture chlorophyll.

Apply sequestered iron,diluted as instructed,mulch around the base of the bush,when the soil is moist,using well rotted manure,peat or compost.

Feed with any propriertary rose food and spray as before,the treatment used will not cause .this problem.

Vine weevils may have attacked the roots,carefully pull away a little soil and look for small,white grubs.

Drench with a suitable insecticide,your horticultural office will advise what's best for your zone.

Answer 3

neither would have caused it.   You say lower leaves,  what is under the plant? grass? dirt?  Look for the culprirt there since you didnt say the plant itself was unhealthy