Being in not too dissimilar conditions I can feed back re my experiments of growing in boggy ground - my soft fruit seems to be fine - rasps, blackcurrants, redcurrants, blueberries, strawbs - all good, rhubarb - yep, cranberries - not doing much but i think were slightly strangled by overgrown grass so have moved them. Willow, alder, hazel, elder - all going great guns. I've put a mixed hedge on top of a bank so it's not nearly so wet there but i think it would be fine in the damper areas - includes hawthorn, blackthorn, rosa, elder etc. I find mulching really helps too.
Trying to plant veg straight into the ground - not so positive. I've resorted to building raised beds out of scrap wood left over from housebuilding - they're not posh and they certainly ain't fancy - only 2 planks high and defo makes a difference - oh and they're certainly not straight, lol. Lavender - pretty much rots off - I've moved it to a stony drier place - much better. All my herbs are in pots although lady's mantle, lemon balm and mints will grow anywhere - they are a bit thuggish tho so watch 'em. I've heardthe large lidl bags make good grow bags for spuds - I would defo grow your spubs in bags - the slugs are a pain in the *** here!
Windburn and salt air/spray is prob another joy you have to overcome as well in your location.
Good luck, let us know how you get on
