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Hello and welcome.
Where in the west midlands are you ?
Do you have somewhere to overwinter plants since they are in pots ?
What Bananas /palms are they ?
They do need a mild shady spot. Acid to neutral soil. Dislike cold drying wind and wind chill is the biggest killer and can turn leaves brown. Hope this may be of help
They prefer rich damp soil . Are not fully frost hardy and may need additional protection in winter or moved indoors/greenhouse
cabbage palm usually refers to cordyline which is not a palm at all
or Sabal palmento they are both quite different to each other.
The cordyline as strap like leaves whilst the sabal as palm like fronds