Most of my roses are this size or larger, so I have lots of experience pruning big roses. I would only trim the long canes now that are shooting out to keep them from whipping around this winter. Then in spring do the real pruning, maybe using a book just for basic guidance; there are no hard and fast rules for me. A large shrub can be pruned just like a smaller plant. Believe me, roses respond well to pruning, and I don't think you'll overprune your rose. I garden in zone 7, so I like to do my pruning in the middle to late March. I don't follow hard and fast rules--I want a pleasing look; no canes whipping around or rubbing against each other. Anything totally dead should be removed, but I wait on canes that have some dark areas to see if the cane stays good as the season progresses. Shrub roses are usually not pruned as hard as hybrid teas, but I go by instinct, which you will acquire as you have more experience. Do you know what your rose is? It looks like a shrub, for sure. Diane

Do you have photos of the bush in bloom? I think it might be good to know what kind of rose you've got there before going in too hard with the pruners.

Some roses only bloom on old wood, so don't prune now. Post photos when it blooms.

Oh, is that Dr. Huey?

The photos and other info weren't up when I posted. I think it's Dr Huey, since it bloomed only in April it sounds like. You have a rootstock there, probably because the rose that was grafted to the rootstock (the desirable rose) has died and Dr Huey remains. This is a once blooming rose that's very prone to fungal diseases. Most people do not want to grow it. Diane

Ah, well, since it's not my house I'll still do my best to keep it alive and looking as good as possible. It hasn't really shown signs of fungal disease, at least. Now I just need to decide whether to trim or train it I guess. Thanks for the intel!

You can trim it if it's in the way of you opening your gate or whatever. That thing won't die. Assuming you are allowed to.

If you want flowers, train it, don't trim it. Dr. Huey blooms on old wood, so if you prune it like a hybrid tea, you will cut off all the flower buds.

Prune it to the shape you would like at any time of year. We have Dr. Huey and it is not hurt one bit by pruning. It doesn't get diseases here and is very healthy. It will throw 12 ft canes that get in the way of the walk way so we always cut those off and tied some up. The flower production in the spring was never hurt, likely because there was so much of it.

We are about to prune off some long throw canes from our Dr. Huey.

You just get more blooms if you don't prune now.

@Stephanie, 9b inland SoCal That photo is beautiful.

This was our Dr. Huey. You can see how it would impinged on our walking space with out pruning all through the summer.

We would lop off unwanted canes all summer long. Had to do it to keep it safe to walk by.