I'm wondering what you mean by orange blossom, Kimmi - Philadelphus? If so, that should really be pruned after its finished flowering, much earlier in the year. Suggest you leave it now till winter, when the plant is completely dormant, and cut it back then - but you will lose the flowers next year. The other alternative is to wait for the flowers in 2012 and then give it a good hard prune immediately afterwards.