Maderense comes from Madeira, the Portugese islands off Africa. So hopefully you live in a warmer section of the UK. Delonix1 took his photos in San Diego, which has similar temperatures to Madeira and, of course, the Azores.No trimming beyond deadheading, although mine usually die after flowering. No problem, I let the seeds ripen and then scatter them, and I get plenty of new plants. I have also found that they don't like to be moved.

RHS advice is that the're not hardy in the UK. Your plant would have to be in a very sheltered and south facing position in the very mildest area to survive - as any lower temps, let alone a touch of frost will kill it, June. Sorry about the bad news - they are lovely plants. I hope you can get some seeds from it to grow more of them.

I've tried leaving this plant in the garden in temperate Cornwall and lost it in winter both times - and not particularly harsh winters. I didn't find that is self seeded here either. Best take it indoors Beggars.
And welcome to GoY :-)

They are biannual, so maybe you would have to use a large pot.