Short-toothed mountain mint

A low, clump-forming native woodland violet of eastern North America, grown for its early spring blue-to-purple flowers with conspicuous white throats held over glossy, heart-shaped leaves. It does not run, but self-seeds freely - to the point of being weedy in rich, moist ground. A larval host for fritillary butterflies and a nectar source for early bees and butterflies; the leaves are high in vitamins A and C.

The first thing to settle about plains coreopsis is the thing seed racks are vaguest about: it is an ANNUAL. Missouri Botanical Garden types it that way without hedging, the Lady Bird Johnson Wildflower Center calls it an annual in its first line, and the plant germinates, flowers, sets seed and dies inside one season. That single fact separates it from the other two coreopsis in this group. Lanceleaf coreopsis and largeflower coreopsis are true perennials that gardeners routinely expect to be long-lived and that are not quite: MBG says lanceleaf needs dividing every two or three years in a border to stay robust; threadleaf coreopsis, already in this catalogue, is the one that genuinely persists. Plains coreopsis persists differently - not as a plant but as a seed bank. It self-sows heavily, and a stand that looks permanent after five years is five generations, not one plant, which is why it is the coreopsis for a meadow sowing and the wrong one for a slot in a border where something has to be there next April. What you get for accepting that is the best flower in the genus for the money. Solitary daisies one to two inches across, seven to nine bright yellow rays each painted maroon at the base around a red-brown disc, carried in quantity on wiry branching stems above finely cut foliage. MBG rates it showy and good for cutting, lists no serious insect or disease problems, and puts its maintenance at low. It is the plant behind most of the yellow in a roadside wildflower mix. Two cautions belong next to that. It self-seeds hard enough that MBG recommends deadheading specifically to prevent it, and it has naturalised across nearly fifty territories outside its home range, from Britain and Poland to Japan, Java and Fiji - so treat spare seed as something to bin rather than scatter. And the two best sources disagree about water: MBG grows it dry to medium and calls it drought tolerant, while the Wildflower Center rates its water use HIGH and says the good years are the wet ones. Both are describing the same plant honestly, and the record below explains why.

The original black-eyed Susan - a bristly-stemmed, short-lived meadow daisy that behaves as an annual, biennial, or brief perennial depending on where it grows. It blooms hard and early from seed, then carries itself forward by reseeding rather than by spreading into a permanent clump.

A native upright perennial with fragrant midsummer flower panicles in pink, white, lavender, or red - a classic border anchor and hummingbird-friendly choice for sunny beds.

A clump-forming native perennial of the carrot family that opens flat-topped, compound umbels of tiny golden-yellow flowers in late spring, when little else is blooming. The toothed, twice-divided-in-threes (biternate) foliage and the bare central flower stalk on each umbel set it apart from other umbellifers. A documented larval host for the black swallowtail and an early-season nectar and pollen source for short-tongued native bees.

Largeflower tickseed is sold as a perennial and behaves like one for about two years. Missouri Botanical Garden says plainly that the plants are somewhat short-lived and that self-seeding is what perpetuates a good planting; the Lady Bird Johnson Wildflower Center is blunter still, recording that it is not reliably perennial and self-sows readily, becoming weedy. Those are two descriptions of the same plant, and believing them is the whole difference between a stand that lasts and an expensive annual. What you are buying is a seed-perpetuated colony rather than a long-lived clump: the original crowns thin out after two or three seasons and volunteers carry the planting on, which means it survives only where there is bare soil to germinate in and where some flowers are allowed to set seed. Deadhead every head, every year, and the colony ends when the crowns do. The flowers are the largest of the common yellow tickseeds, 2 to 3 inches across, deep yellow rays notched at the tips around a darker golden disc, held one to a stem on slender erect stalks to about 24 inches. What it wants is the opposite of border hospitality: poor sandy or rocky soil with sharp drainage, full sun, and no irrigation. Missouri Botanical Garden records it as tolerant of heat, humidity and drought and names crown rot in moist, poorly drained soil as the way it dies, so the reliable method of killing it is kindness. Within this catalog it sits between plains coreopsis (Coreopsis tinctoria), a true annual that never pretends otherwise, and lanceleaf coreopsis (Coreopsis lanceolata), the other short-lived perennial and the plant it is most often mislabelled as. The leaves settle it: lanceleaf carries narrow, hairy, unlobed lance-shaped leaves gathered in a basal tuft, while largeflower has lobeless linear leaves at the base and pinnatifid, deeply lobed upper leaves cut into linear segments up the stem.