A pot rose when to plant into the ground?

[NinNinJin]

I have two roses one has already spent a year in a pot and flowered beautifully. The other one is a root.
When shall I put them in the ground?
And what spot in the garden shall I choose? The front garden would be good but it only gets afternoon sunshine otherwise it is very shady. West facing.
Back garden gets very hot in the summer. Almost no shade. South-east facing.

I planted the one I got for Christmas last week before the frosts.
However, you might want to wait until it warms a little otherwise it might be too hard to dig a hole now the ground is frozen.
if you know what varieties your roses are I’d have a google. Some are suitable for shade (although they still prefer a few hours sun a day) but most do better with more sun. You’ll need to keep them well watered this summer so they have a chance to establish a good root system.

If it’s been indoors you’d have to acclimatise it to lower temperatures

@MereDintofPandiculation both are in the pots outdoors

In which case, plant whenever's convenient to you. You've basically got a "container grown plant" like you'd buy from the garden centre. Probably not in frost (because you disturb the soi land get the cold layer at the top mixed up with the warm layer underneath. All other things being equal, I'd go for about March, when it's preparing to be in growth again and can repair any root damage. Water it for its first year.

March or April as much sun as possible for roses.