I have often heard that you prune when the forsythia are blooming, but I like the idea of actually looking at the roses when determining when to prune. I like to prune when I first see the leaf buds starting to swell. I am not that familiar with forsythia, and some may bloom earlier than others, and some roses may develop earlier or later than others, so my theory is that it is better to actually go by the condition of the plant you are pruning.
Here is a good description of spring rose pruning.
http://www.gardensmart.tv/?p=a...
