aka eastern waterleaf; Hydrophyllum virginianum
and aka maple-leaved waterleaf; Hydrophyllum canadense
Hydrophyllaceae
(some authorities place in Boraginaceae)

So you might be wondering, which species is pictured above?  I know the answer, but only because I took the picture.  The flowers of both species are almost identical.  The big difference is in the leaves.

Virginia waterleaf typically has three to seven deeply cut lobes…

…while the other resembles a maple leaf, with much shallower lobes.

Virginia waterleaf starts blooming in the Potomac Gorge around mid-May; broad-leaved starts about two weeks later.

Of the nine species of Hydrophyllum found across most of the US and Canada, these are the only two in the Maryland Piedmont.

Look closely at the leaves at the bottom of the picture – see the bluish splotches? That’s why they’re called “waterleaf”.  Only the young leaves display this characteristic.

Virginia waterleaf ranges from the Great Plains east to the coast, except the extreme south and the Maritime Provinces.  It’s a plant of special concern in Connecticut and Kentucky, and is threatened in New Hampshire and Tennessee.

Maple-leaved waterleaf has a similar range, but doesn’t extend as far west. It’s endangered in Massachusetts and New Jersey, and threatened in Vermont.

Both species are plants of deep woods, liking lots of shade and moist-to-dry, high organic content soils.  And both species’ flower color ranges from white to pink to lavender.  At bloom time, they are about the same height (around a foot), though I’ve noticed that Virginia waterleaf grows much taller than that once it’s done flowering.