Spray with a natural product like the one at
http://www.natural-ant-killer.com

It won't harm your roses or the environment. In fact a side benefit to
this product is that is also works as a natural fertilizer!

I have personally used it on my lawn and no longer have any pesty
pests. And my lawn looks terrific!

They tell me that the way it works is that it contains an natural
surfactant that breaks water molecules in molecules that are so tiny
that they penetrate the waxy coating of critters and it drowns them
instantly!

Because it breaks down water into smaller molecules, it gets down into
the soil better and as a result my lawn and plants flourished!

I am estatic!