Hi Cuts and Grazes! I can only offer my own personal experience of growing in this type of situation. I have some boggy areas in my garden which will flood during rainy weather but also get a bit dry during very dry spells (though not absolutely bone dry...and if yours does, you may need to water). Here are some that are thriving....

Honeysuckle, Geum Rivale, Lobelia 'Victoria', Sanguisorba, Iris Sibirica, Hosta, Hemerocallis, Some grasses like Luzula Nivea and Carex Pendula, Photinia 'Pink Marble', Potentilla (herbaceous kind, not shrubby), Ferns, Astilbe, Primula Bulleyana, Houttuynia Cordata, Zantedeschia

Hope this gives you a few options to at least try. Might it be possible to improve the drainage in that area at all, by double digging and adding some grit? It is a horrible problem, I know only too well!

I've put a carex pendula in just such a situation and have since been warned off it as apparently it seeds everywhere. It would be nice to find a similar one that is more well behaved.

Yes, it would Steragram..sorry I'm new to grasses. I do have a wonderful Stipa Gigantea, but I don't know if it would tolerate the wet. Still, sometimes it just pays to try!

Thanks to you all for your help. I too know little about grasses but if the carex is the one I think it is then you are right Steragram, it does seed everywhere and have you ever tried to dig a mature one out. This highlights the situation that some plants should never be sold by garden centres unless you really know what they are.

I am about to try to dig a mature one out after all the warnings I've had! So disappointing because I really do like it and apart from mint its the first plant that's been happy in that spot.. But can't blame the garden centre as it was given to me.

I'm sure I planted one near my pond, but in this weather, I can't locate it to get it out before it starts getting it's roots down!....maybe next week! :D

I spent years digging out seedlings from a Carex Pendula and agree entirely with all the comments. The original was huge and it did look good but would never buy another. In fact now avoid Carex altogether. One of my My favourites is Miscanthus Sinensis 'Silberspinne (Silver Spider) which I planted in 2001 so now v.large; early this year I dug out a nice clump for a friend.
Linmar

I got the Carex out, split it in two and planted it in a bog! Hopefully it will grow there where nothing else seems to want to except for weeds!