Kristi...I haven't a clue about oven temps for drying...I would guess it would have to be pretty low. Most people tie the branches in a bundle and hang them to dry..then when they are dry you just remove the "leaves" from the branch. I always end up doing things a crazy way...what I do is remove the "leaves" first..then I have tiny mesh(screen) wire baskets that I put all of the leaves in and let them dry...but if you are doing a bunch at one time you have to be sure to turn them everyday to assure they don't mildew from the moisture in the leaves at the bottom. A lot of people use them as they are...I prefer to put them in my chopper and cut them til they are almost a powder. I rarely ever use fresh rosemary any more because the flavor of the dry is so much better/stronger. that is what I give all of my family for Christmas...dried herbs from my garden (along with
pepper sauce, salsa etc.) from the other things in the garden. Dried rosemary can be expensive to buy...and then you never know the quality or freshness. That is why I have so many rosemary bushes. I also have one planted at the cemetery where my son is burried...rosemary is the herb of remembrence..so it is special to me
. Hope this long drawn out explanation helps some...you ought to have quite a bit to work with from your bush...it is beautiful...but will look great trimmed back.