I see no reason the gardener should desire an area of boggy ground, but here there is a rather large area that borders the garden that is constantly damp. I presume the source of the moisture is a spring that is in close proximity or perhaps beneath the garden shed.
The spring dampens the forested area just beyond the boundary of the property, and a noticeable flow winds from here to the rear of the garden. The volume of water has varied over thirty one years that this garden has been tended, but in the recent decade the flow increased to kill a large holly and a prized witch hazel.
The damp area within the garden has been replanted with a moisture tolerant Sweetbay magnolia (Magnolia virginiana) and a variety of shrubs and perennials. A wide spreading, pendulous form of bald cypress (Taxodium distichum ‘Cascade Falls’) is quite happy in swampy ground, and soon will require regular trimming to prevent it from occupying too much space. I suppose that the whole of the planting is a year away from being satisfactory, but this is a considerable improvement from a few years ago when everything was chopped out and started nearly from scratch.
The damp woodland is home to a patch of native Ostrich ferns (Matteuccia struthiopteris), with a few pilfered years ago to start a clump in a much drier and sunnier setting where the fern must regularly be chopped back. Just beside the patch of Ostrich ferns are scattered clumps of the marvelous Skunk cabbage (Symplocarpus foetidus, below). I claim no role in starting these, but from late winter into spring the Skunk cabbages are a curiosity.
Ramblin' through Dave's Garden 
In a chaparral or desert climate, a bit of boggy ground is actually an asset, where we can grow a few riparian species. It is nice if it drains though. We work around two creeks and three springs. Even though the riparian areas are very narrow, they are nice for species that would need irrigation in other parts of the landscapes. The native redwoods do not mind, and take centuries to adapt to whatever their soil happens to be.
I’d love some ideas for dry shade. I took notice of the bottlebrush buckeye pictured above. Does it thrive in our dense VA ground? And where could I buy a specimen that’s more than 3 inches tall or bare root? I have an area in dry shade that is virgin woodland, so packed soil with lots of roots from mature trees and understory saplings. But it’s close to my kitchen window so I NEED to make it more attractive.
Bottlebrush buckeye is happiest in damper ground, but the one I’ve planted in drier shade shows no ill effect. Practically, it must be watered for the first year, but it will grow and flower without a problem. It is somewhat unusual to find in a garden center. I don’t know where you live, but Meadows Farms garden centers should have bushy 4-5 foot this spring.