Northern Buckwheat, also known as heart-leaf buckwheat is a woody, loosely branched shrublet, sometimes erect, sometimes prostrate. Plants may attain a height of 25-40 cm in bloom, and 60 cm in diameter. The leaves, depending on the variety, may be heart-shaped, ovate, or broadly lanceolate. The leaves are characteristically very white or woolly below and less so to more greenish above. The petioles are roughly as long as (to twice as long) the blades which range from 7-25 cm long and 1.5-5 cm wide. The stout, erect flower stems lack leaves except for several thin bracts directly below the point where the stem branches out to support the wide flower heads.
The inflorescence is a wide cluster or umbel from 2-20 cm wide atop the hollow stems. The 4-10 rays of the umbel range from 2-5 cm long. The flower color varies from a creamy white to a deep lemon-yellow. The involucres range from glabrous to tomentose with triangular lobes about one-half as long as the involucre, which is 6-10 mm long.
Variety compositum: Leaf blades ovate to deltoid, often with a heart-shaped base. Involucres sparsely to densely woolly. Found from Mt. Rainier east across south-central and southeastern Washington and south through Oregon to northern California. It may also occasionally be found west of the Cascade Mts. in the Willamette Valley.
Variety lancifolium: Leaf blades lanceolate, usually more than 3 times long as wide. Found in the Wenatchee Mts. of southern Chelan County, and occasionally into northern Kittitas County in Washington.
Variety leianthum: Leaf blades ovate to deltoid, infrequently with a heart-shaped base. Found along the east slope of the Cascade Mts of Washington to the south of the Wenatchee Mts south to Mt. Rainier and east through much of central Washington to west-central Idaho and to Baker County in northeastern Oregon.
Heartleaf Buckwheat is typically found on dry open, rocky slopes, frequently on talus or cliffsides.
Heartleaf Buckwheat is primarily found east of the Cascade crest, from Washington's Chelan County in the north to northern California, eastward Nez Perce County of Idaho, south to northeast Oregon. It is also found in the Umpqua Valley of southwest Oregon and may be found on undisturbed, rocky islets on the upper Willamette River.
Heartleaf Buckwheat is a relatively easy buckwheat for the rock garden. It's foliage adds a nice silvery hue to the front of the garden, and its white or yellow flowers are additionally choice (and highly insect attractive) although prone to flopping as they get larger. One of mine was exposed to near record rains in Portland this past year, and survived fine, although it looked dead early in the spring (all of the leaves shriveled up).