Going to be very boring and say wait. you need to know if it dries in summer, some of my
land dries out
enough to be walk-able in summer and some is even dig-able and plant-able, but other bits never dry out and are constantly either covered or saturated. I do have reedbeds and to be honest they are boring and invasive, we have shallow ponds, a couple of springs, one of which grows watercress, and the rest is wet meadow. so rushes, meadowsweet, bog avens, some umbelifers the bottom is wet enough that grass is not really happy and we only have a couple of wet tolerant species. also willow, alder and rowen
trees manage. None of our trees in the wet areas get big, as the top soil is shallow and is underlain by solid clay which no
roots can penetrate (and is also the reason why it is wet) So strong winds bring them down regularly.
We do actually have a bog garden.. in one of the
dryer areas, most plants sold for bog gardens only like to be moist not soaked, and especially not soaked over winter and then frozen solid.