My overgrown rose is completely out of the place. It is in the wrong place of the garden and it is the only tall plant (around 6ft) in the middle of low border so even though it flowers beautifully, the location is awkward.
If I cut it down to a small trunk, then only a multiple mature trunk will remain which is leaning towards the fence and is pushing the fence rather than standing straight.
Is there any way straighten, or move to another location safely?
Or should I just cut it to 2-3ft to match with the height of the border?
Depends on the rose a bit but you could move it if you're quick.
Is it a 'standard' rose - i.e. like a lollipop with a single straight trunk and a bushy flowering bit at the top? or one that bushes out from the ground level with several smaller branches?
Dig and prepare a hole ready for it where you want it to go, then if it's bushy with several stems cut it right back to 6-8" or so, dig it up with as much root as you can get, pop it in the new hole with the graft point an inch or two underground (this is the point where the roots join with the above ground bits), backfill it and water it in. Should be absolutely fine. If it's a lollipop then I'm not so sure, I'd move it anyway and cut the lollipop bits back but not the main stem.
PS - do NOT cut it to 2-3ft 'to match the border' it will just grow to 6' again. If you cut it back to make it short then cut it back to 6-8". But if it's an 'old rose' (i.e. historical variety not just one that's been in for a few years) you may lose the flowers.