Plants with white flowers
 Prenanthes alba (Prenanthes alba) |
 Prenanthes racemosa (Glacuous White Lettuce) |
 Prosartes trachycarpa (Fairybells) |
 Prunus pensylvanica (Pin Cherry) |
 Prunus pumila (Sand Cherry) |
 Prunus virginiana (Choke Cherry) |
 Psilocarphus brevissimus var. brevissimus (Dwarf Woolly-Heads) |
 Pterospora andromedea (Pinedrops) |
 Pyrola chlorantha (Greenish-Flowered Wintergreen) |
 Pyrola elliptica (Common Shinleaf) |
 Ranunculus aquatilis (White Watercrowfoot) |
 Rhododendron groenlandicum (Labrador Tea) |
 Ribes glandulosum (Skunk Currant) |
 Ribes hudsonianum (Northern Black Currant) |
 Ribes oxyacanthoides (Northern Gooseberry) |
 Rubus chamaemorus (Cloudberry) |
 Rubus idaeus (Wild Raspberry) |
 Rubus pubescens (Dewberry) |
 Sagittaria cuneata (Arrowhead) |
 Sagittaria latifolia (Broad-Leaved Arrowhead) |
 Sambucus racemosa var. racemosa (Red Elderberry) |
 Sanicula marilandica (Snakeroot) |
 Saponaria officinalis (Bouncing-Bet) |
 Sibbaldiopsis tridentata (Three-Toothed Cinquefoil) |
 Silene csereii (Smooth Catchfly) |
 Silene latifolia (White Cockle) |
 Silene menziesii (Menzies' Catchfly) |
 Silene noctiflora (Night-flowering Catchfly) |
 Sisyrinchium septentrionale (Northern Blue-eyed Grass) |
 Sium suave (Water Parsnip) |
 Smilax lasioneura (Carrionflower) |
 Solanum triflorum (Wild Tomato) |
 Solidago ptarmicoides (White Upland Goldenrod) |
 Sparganium angustifolium (Narrow-leaved Bur-reed) |
 Sparganium eurycarpum (Broad-fruited Bur-reed) |
 Sparganium natans (Small Bur-reed) |
 Spiraea alba (Narrow-Leaved Meadowsweet) |
 Spiraea betulifolia (Shining-Leaved Meadowsweet) |
 Spiranthes lacera (Slender Ladies'-Tresses) |
 Spiranthes romanzoffiana (Hooded Ladies'-Tresses) |