Culture
Easily grown in peaty woodland soils in full sun to part shade. Tolerates close to full shade. Prefers part shade and dry soil conditions. Established plants have good tolerance for drought. Easy to propagate by seed.
Noteworthy Characteristics
Taenidia integerrima, commonly known as yellow pimpernel, is an herbaceous yellow-flowered member of the carrot family that is native to rocky slopes, hillsides, open woods, thickets, prairies and bluff ledges from Quebec to Ontario to Minnesota south to Georgia and Texas. It typically grows to 3’ tall, producing yellow flowers in umbels into the heat of the summer (May-July) on smooth, glaucous, green to reddish-brown stems clad with compound leaves whose dull green leaflets have entire margins.
Long-stalked lower leaves (to 12” long and to 6” wide) are double to triple compound in groups of 3 to 5 leaflets, whereas the upper leaves are single to double compound in groups of 3 leaflets. Upper leaves sheath the stem. Ovate to elliptic leaflets typically grow to 1” long and to 1/3” wide. Foliage has an aroma reminiscent of celery when crushed.
Tiny, yellow, 5-parted flowers (to 1/8” across) bloom in open airy umbels (3-7” across). Each large umbel consists of about 10-16 small, long-stalked, well-spaced umbellets. Flowers give way to flattened, wingless, longitudinally-ribbed fruits (each to 1/6” long).
Caterpillars of the black swallowtail butterfly and Ozark swallowtail butterfly feed on the foliage of this plant.
Synonymous with and formerly known as Zizia integerrima.
Genus name comes from the Greek word tainidion meaning a little band in apparent reference to the low ribs of its fruits.
Specific epithet from Latin means most entire in reference to the smooth leaflet margins (most other carrot family members have toothed leaflets).
Problems
No serious insect or disease problems.
Uses
Woodland gardens. Native plant gardens. Not commonly found in cultivation.