Roses

[derrynoose]

I know little or nothing about the gowing of roses, but moved a four year old bush for a friend in the spring time. It has just started to flower but I notice that on some leaves there are small brown dead-looking or rustlike spots whilst on others there are small circular holes. What can I do to prevent these getting worse? Thanks.

[Clanad]

Ah ha! Two for one. Please see the answer given just a few questions up.

You do not have Black Spot, but rather Powdery Mildew, but the causes and final results will be the same.

You could use the same chemical compound recommended for Black Spot, but I've found, at least here in the U.S. that a dry application works better for this type of fungus. I'd recommend Thiophanatemethyl in a powder for control. One brand name I find effective is Halt Ornamental Fungicide It comes in a tall cardboard tube and can be applied by squeezing the sides fo the tube quickly to apply a fine dust film on the plant.

Any garden supply store can sell you this or another effective control.

Again, be sure to remove any infected brances and leaves, clean it up around the base and apply the dust. Be careful not to breathe it. Repeat at 7 day intervals at least for a month or until the infestation is controlled...