I agree that September is a good time to fertilize. And up here October is a good time to prepare for frost.
I sprayed my roses with Freeze Pruf and all the new foliage that came out at the end of September is still happy despite our getting frost for most nights over the last ten days. Maman Cochet is growing like mad... which makes me worry. Frost can kinda creep up on you: I think it killed my two year old brugmansia.
