Lucas Land
Shalebarren Evening Primrose
Oenothera argillicola
A showy biennial that can reach 60 in. in height. Its erect or ascending stems are smooth and grow from strong fleshy roots. The leaves grow both basally and alternately along the stem. Stem leaves are narrowly lanceshaped, up to 3/8 in. wide, 7 in. long. Leaves are glossy, dark green and sometimes finely hairy. The yellow flowers usually last only one. Each flower has a round ovary and 4 overlapping petals that are 3/4 to 1.5 in long. Flowers are displayed from July through September in a spikelike cluster that droops at the top.