A herbaceous plant is a plant that has leaves and stems that die down at the end of the growing season to the soil level.
A good drought tolerant ground cover for use in a border, in a xeristrip or a rock garden. Evergreen grayish green leaves with fine hairs (tomentose). Will grow too tall and gangling in too rich and moist a soil. Some areas of the country have noted Cerastium tomentosum to be invasive, but I have not seen those tendencies here. A good substitute for the annual alyssium. Cerastium tomentosum var. columnae is a commonly available variety.
Perennial with lyre shaped leaves, similar in appearance to scabiosa, native to central Europe. In fact, it's synonym is Scabiosa rumelica. Deep purple red pincushion-like flowers. Knautia macedonica may suffer from our alkaline soil if not well amended with compost and well drained. Will reseed some. Has a pleasant wild look. Popular with nectar feeding insects. Deadheading doesn’t seem to be necessary.
Another old garden perennial that’s still good for our Panhandle cottage gardens, Physotegia virginiana is native to eastern and southeastern US. A terrific addition to the late summer and fall garden. Comes in three pleasing colors of light pink, purplish pink and a real pretty white. The white variety "Miss Manners' and 'Summer Snow' are both better mannered, not spreading quite as vigorously. It's native habitat is in moist, rich soils, but keeping it on the lean side makes it more "obedient".
Lady in Black aster is an improved selection over the Midwestern native, Aster lateriflorus (now Symphyotrichum lateriflorus). Dark canes with musty purple leaves provide a striking contrast in the flower beds and borders that become covered with tiny white aster flowers with pink centers. Truly stunning bee and butterfly magnet for about 3 weeks in autumn.
Similar in form to Callirhoe involucrata, Callirhoe alcaeoides 'Logan Calhoun' grows natively from the Midwest to southern plains. While Callirhoe alcaeoides can be pink, to pale pink and pale lilac, 'Logan Calhoun' is pure white. Spreads over an area similar to wine cups, the foliage and flowers are finer. I've found it to be drought tolerant; water monthly to insure continued blooms. Blooms will rest during the heat of the summer and continue following rains or cooler weather.
Gooseberryleaf globemallow is very close in appearance to scarlet globemallow, Sphaeralcea coccinea, but much taller, up over 2 feet. The leaves are silver green and hairy, resembling the leaves of the current shrubs in shape, so named from the family name of currents and gooseberries, Grossulariaceae. Flowers are orange in color and bloom from May and June, sometimes later in the summer. Native to hot, dry areas semi-arid regions throughout the Southwest and the Great Basin Desert. Prefers good to sharp drainage.