On 05/08/2013 23:48, Bob Hobden wrote:
"Roger Tonkin" wrote

A friend has a problem with roses that live in large pots outside the
front door, next to a busy road.

For years they have flowered strongly, but this year a lot of the
leaves have turnedbrown and dry on the outside, yellow in the middle,
but remained green on the central vein.

They are only very small leaves, and I did not have a camera when I
saw them. Not been able to find anything similar by googling so far,
so any one any ideas please?


Phytophthora? Roses are susceptible.





It sounds to me more like a combination of chlorosis (yellow with green
veining) and dryness at the roots (browned leaf edges).

The link below should help.

http://www.marinrose.org/chlorosis.html

--
Spider
from high ground in SE London
gardening on clay