Here's my long list of perennials that require dry (xeric) conditions
~Campanula carpatica~ blue, 8"s x 12"s May-September
~Delosperma 'Mixed Species and Hybrids' ~ mix of species and hybrids, 2"s-3"s high form a spreading mat, various colors
~Dianthus deltoides 'Flashing Light'~ red, 6"s-8"s x 12"s, blooms May-September!
~Limonium gmelinii spp. hungaricum~ (Sea Lavendar) 18-24"s high and wide, mid-summer
~Linaria Auruginea 'Neon Lights' mixed bicolors, 8"s high space 12"s, blooms May-August
~Lychnis viscaria splendens 'ViscaFire'~ fire engine red, 20"s high, forms grassy tufts, May-June
~Penstemon auriberbis~ violet/lavendar, 13"s high x 12"s wide, May/June
~Penstemon barrettiae~ rose-lilac, 9-15"s high x18"s wide, May/June
~Penstemon virens~ (Blue Mist), violet/lavendar, 6-12"s high x 12"s wide, June-July
~Penstemon virgatus (deaveri) 'Blue Buckle', violet blue 10-12"s high x 12-18"s wide, July-September
~Ratibida columnifera subsp. pulcherrima 'Red Midget'~ burgandy and yellow, compact, 18"s x 18"s wide, July-October
~Sedum pilosum~ monocarpic, forms a rosette first year and blooms the second, 3"s high with deep pink flower clusters
.......
~Cotoneaster affinis~ 4 to 6m tall large shrub/small tree, white blooms followed by purple black fruit
~Cotoneaster insignis~ 4 to 5m tall large shrub/small tree
~Eryngium bourgatii 'Mediterranean Sea Holly' ~ 12" to 18" tall white veined learthery leaves, large silvery-blue flower heads
~Glaucium flavum aurantiacum 'Western Europe Yellow Hornpoppy' ~ 20" high, rosette deeply-cut, blue/grey,
large burnt orange poppy-like blooms followed by long seed 'horns'
~Gypsophila repens 'Creeping Baby's Breath'~ 8" tall and wide gray/green foliage masses of white flowers in early summer, cut back for rebloom in fall
~Heliopsis helianthoides (variegata) ~150cm tall, dark green veining on a white leaf. The same yellow flowers and very long bloom period as the species
~Jasione perennis (laevis) ~ 12" tall when in bloom, succession of dense 2" balls of misty blue flowers from June to August
~Hudsonia ericoides ~ 'Pine Barren Goldenheather' ~ 8" to 12" mat-forming shrub, scale-like foliage, small bright yellow flowers in summer.
~Limonium latifolium 12" to 24" ~ low mound of leathery green foliage, blooms lavendar-blue
~Lychnis viscaria ~ 'German Catchfly' ~ 18" grass-like tufts and long stems bearing clusters of purplish-pink flowers. Long blooming in early summer.
~Pulsatilla vulgaris 'Red Form'~ 12" ~ red/maroon flowers,
~Salvia jurisicii ~ 12" to 18"~ tall fine feathery foliage, spikes of hairy, upside-down blue flowers in late spring.
~Sophora davidii ~ 2.5m tall shrub with spiny stems, and pea-like foliage, racemes of purple-blue and white flowers in early summer.
~Stachys macrantha ~ 12" to 24" tall, wrinkled leaves in a mound, erect, densely packed spikes of purple-rose flowers
~Stipa pennata ~ forming 18" clumps of very fine-textured green foliage, above which form clouds of silvery flowers that move in the slightest breeze
~Strobilanthes atropurpureus ~ rare member of the acanthus family native to woodland margins in the Himalayas and Siberia.
Mid-summer until frost the plant is smothered with dense spikes of purple-blue tubular flowers, resembling Salvia.
Best in bright shade or morning sun with afternoon shade
~Taraxum pseudoroseum ~ 6" to 8", a dandelion which is a perennial species native to Asia, growing in alpine meadows.
Pink flowers with a yellow center bloom over a long period in spring
~TRADESCANTIA ohioensis ~ 'Ohio Spiderwort'~ 12" to 48" a hot, dry spot, and don't grow it anywhere else or you will never really see it at it's best! Beautiful, clear-blue flowers over distinctive grey-green foliage, which colours purple in cooler weather
There's lots of people here that do know!