There are quite a few shade tolerant, shade loving plants suitable for ponds and water gardens, you may want to think twice about spatterdocks as they tend to be very large sprawly plants six feet wide
There are a couple of small forms of spatterdock (very nice plants) Cape Fear Spatterdock, and Nuphar Pumilla Minima. That always has a place here in favourite shady ponds...
Aquatic shade tolerant plants:
(prefer saturated soil conditions, water over their roots)...
Alisma, Acorus calamus, acorus calamus variegatus, arrow arum, arrowhead, Azolla, Bladderwort, Bog Arum- calla palustris, Cotton grass, Cyperus longus, Eleocharis (spike rush), equesetum hyemale, frogbit, Golden club, Hornwort, Horsetail, Iris (shade may reduce their ability to flower some) Carex sedges, Lizards tail, Mares tail, Marsh marigold, Marsh pennywort, Marsilea, Nuphar pumilla minima, Parrots feather, Pennywort, Nymphiodes aquatica, Phalaris, Scirpus zebrinus, Typha (not the nasty latifolia, way too invasive) Water hawthorn, Water Lettuce, Water mint ...theres GAZILLIONS of shade loving aquatic and bog plants
Bog plants:
(Prefer moist but not saturated soil conditions)
Acer, Aconitum, Alchemila, Alliums, Arum lilies, Aruncus, Arundinaria, Astilbe, Azalea, Berberis, Bergenia, Brunnera, Carex pendula, Chamaecyparis, Cimicifuga, Cinnamon fern, creeping jenny, Ferns (Many), Convallaria, Corylus, Cotton grass, Cornus, Cotula, Cyclamen, Danae, Dicentra, Epimedium, Euonymus, Filipendula, Fritillaria, Galium, Gentiana, Gunnera, Helleborus, Hemerocallis, Hemp agrimony, Hepatica, Heucherella, Hosta, Hydrangea, Ligularia, Liriope, Lisichiton, Lilium, Lonicera, Lupinus, Lychnis, Lythrum, Meconopsis, Mimulus, Miscanthus, Peltiphylum (Darmera) Phyllostachys, Polygonum, Primula, Ranunculus, Rhamnus, Rheum, Rhododendron, Rodgersia, Royal Fern, Rubus, Sasa veitchii, Saxifraga, Senecio, Sinarundinaria, Sium suave, Skullcap, Tellima, Viola, Weigela
half hardy (need wintering frost free)
Cyperus Alternifolia, Crinum Americanum, Gymnocoronum spilanthoides, Cyperus papyrus, Arum lilies (callas) Marselia, Taro, Salvinia, Umbrella grass
I list some full aquatics as well as bog plants. There's enough plants mentioned above to cram many a pool, bog, water margin... arrow arum alone likes to make an exotic foliage plant 3 foot high, and 3ft wide when it has conditions it likes... Many of them are 'specimen plants' ...in effect they are gobsmackers.
Regards, andy
http://www.pinterest.com/adavisus/pondering/