Posted: 16/01/2014 at 12:23
Some of the above but Pseudopanax is not that hardy (-5 at most) so I would not plant in County Durham. The one with the large leaf look is Tetrapanax 'T-Rex' which has leaves over 1 metre. It is hardy, though deciduous after -3C. It bounced back in spring. Fully hardy where you live.
Rheum, Gunnera manicata, giant butterbur are all jungle giants.
Look out for Fatsia taiwania (polycarpa 'needham form'). Far more elegant than bog standard Fatsia. Fatsia moseri is the larger leaf variety, so adds to the exotic look quickly over the species one.
The hardy schefflera are also worthy of any garden and add to the look. Schefflera taiwana rhoddidenrioflora is half-hardy in shelter, possibly lower.
Cordylines are also a necessary.
Bananas - musa basjoo is hardy if protected. Ensete's are hardy if you overwinter frost free.
Trachycarpus winsan and Trachycarpus wagnerianus are the hardiest of the palms.
I agree on Ferns - Dicksonia Antarctica have massive fronds.
Begonia like imperialis, dahlia imperialis etc are all good.
Basically grouping hardy, half hardy and sub-tropical specimen plants will give the look and not the hassle.