They'd be fine in pots Diorrrit, as would all the alstros ..... however, as i've no experience with pots and their specific composts i can't advise further on that score - hopefully someone else will hop in here.
What i will say is that alstros 'hate' wet feet so use composts accordingly.
Also, position them in full sun but not too hot a site (or you'll just get foliage if their roots are always hot).

They do like fast drainage, so I would use a gritty one. An unglazed terra cotta pot would be good, too, because evaporation from the sides will help keep the roots cool.

Thank you both for helping. The spot where I was thinking of putting them gets sun all day long from early morning to late evening and is against a wall so I guess too hot for them? The only other suitable spot is where the sun's on it from early morning until about 1pm. Would that be more suitable do you think?

Possibly, but not necessarily, i have some which are in a very dry sheltered area next to a wall, it faces east and loses the sun about 3ish and mine do very well there.
If you suspect that the soil 'does' stay hot there, then err on the side of caution .... you could do as you'd do with a clematis and shade it's roots - either with a pebble mulch, or other plants foliage etc ..... yes, that's exactly what i'd do, now i think about, it because it'll love the sun but it's feet will stay cool.
Go for it.
If you see they're not happy hike them out and reposition them.

Thank you. I'll try that. I'll probably just buy two to start with and see how they go first.