Brunnera macrophylla ‘Variegata’

‘Gateway’ Joe Pye

Most perennials demand well-drained soil. They perform poorly or die out when in ground that is constantly wet and soggy. However, a small number of perennials tolerate and even thrive in moist soils.  Most plants listed here are all hardy within zones 5-8, and grow best in moist, humus-rich, well-drained soil. Most are okay getting their feet (roots and crown) wet for short time periods in terms of days, but not weeks. The list includes some ornamental grasses that cope with short period of flooding.

Bog plants, cannas, cardinal flower (Lobelia cardinalis), goatsbeard (Aruncus dioicus), monkshead (Aconitum), spiderwort (Tradescantia andersoniana), bugleweed (Ajuga reptans), flag iris (Iris pseudoacorus), Louisiana iris (Iris x hybrida) excel in a continuously wet spot around the water garden or a feature. Papyrus  (Cyperus papyrus). Shrubs like weigela (Weigela floridus), kerria (Kerria japonica), Virginia sweetspire (Itea virginica), smooth hydrangea (H. arborescens), winterberry holly (Ilex verticillata), Joe Pye (Eutrochium spp.), and shrub dogwoods (Cornus spp.).

Perennials to look out for include: Hosta, Siberian bugloss (Brunnera macrophylla), Queen of the Prairie (Filipendula rubra), Toadlily (Tricyrtis formosana), loosestrife (Lysimachia clethroides), plume poppy (Macleaya), Chinese astilbe (Astilbe chinensis), black snakeroot (Cimicifuga racemosa), meadow rue (Thalictrum aquilegifolium),  swamp sunflower (Helianthus angustifolius), obedient plant (Physostegia virginiana), swamp milkweed (Asclepias incarnata), calla lilies (Zantedeschia aethiopica), rodgersia (Rodgersia aesculifolia), primula, rose campion (Lychnus coronaria), Japanese iris (Iris ensata), Indian pink (Spigelia marilandica), ligularias (Ligularia spp.), Farfugium (F. japonicum), swamp hibiscus (Hibiscus coccineus), mukdenia (Mukdenia rossii), and  some ferns including cinnamon fern (Osmundastrum cinnamomeum), royal fern (Osmunda regalis), arborvitae fern (Selaginella braunii), and sensitive fern (Onoclea sensibilis).

Ornamental Grasses for moist sites include hakone grass (Hakonechloa macra), sweet flag (Acorus gramineus), muhly grass (Muhlenbergia capillaris), sea oats (Chasmanthium latifolium), big bluestem (Andropogon gerardii), feather reed grass (Calamagrostis x acutiflora), switchgrass (Panicum virgatum), Bowles’ golden sedge (Carex elata ‘Aurea), Gray’s sedge (Carex grayi), Morrow sedge (Carex morrowii cv.), and common rush (Juncus effusa).