What is this flower?

[Reynard]

I just cut mine back every autumn. They do take a fair bit of abuse.

Mum uses the hips to make rosehip and apple jelly.

 

[furball]

Have you thought about going back to where you bought the rose? Houghton Hall give a five year guarantee on all hardy plants and Dobies give a lifetime (whatever that means) on plants

 

[Tail End Charlie]

I just cut mine back every autumn. They do take a fair bit of abuse.

Mum uses the hips to make rosehip and apple jelly.

Dog roses are great, you can prune them with a chain saw. None of this "third bud to an outward facing whatever" !!
Several stores (Aldi for one round here) seem to use them as a decorative surround to the car park.