Star-of-Bethlehem

Aubrieta (Aubrieta deltoidea) is a low, mat-forming evergreen perennial in the mustard family (Brassicaceae), native to the rocky hillsides of southeastern Europe - primarily Greece, the Aegean Islands, Crete, and adjacent Mediterranean coasts. It is one of the most reliable spring-flowering ground covers for sunny, well-drained spots: cascading sheets of violet to deep pink four-petalled blooms from March through May, attractive to bees and bee flies. The honest catch is that without a hard cut-back immediately after flowering, plants become woody and bare in the centre within two or three years, collapsing from a tight carpet into a tired, gappy mat.

A vigorous, semi-evergreen, clump- and colony-forming hardy geranium grown as one of the best groundcovers for dry shade under trees and shrubs. Its soft, deeply lobed, strongly aromatic leaves form a dense, weed-smothering carpet, many of them flushing red and bronze in autumn, and above the foliage rise loose clusters of magenta-pink (or white) flowers with prominent protruding stamens in late spring and early summer. It spreads steadily by thick surface rhizomes into a tough, low-maintenance, weed-proof mat that is easy to pull back and is not aggressively invasive. The aromatic foliage makes it markedly deer- and rabbit-resistant, and it is genuinely drought-tolerant once established. It is grown purely as an ornamental and is not a food plant.

Felicia amelloides is an evergreen, woody-based perennial subshrub native to a narrow coastal strip of South Africa's Western and Eastern Cape, where it colonises stabilising sand dunes, sandy flats, and rocky outcrops at 0 to 3,280.8 feet. In the garden it delivers a near-continuous flush of sky-blue, yellow-centred daisy flowers on neat mounding growth, typically 12 to 24 inches but capable of reaching about 3.3 feet, making it one of the few true blue-flowered plants for sunny pots and borders. The honest catch is frost-tenderness: it survives only light frost in sharply drained soil and collapses below about 23°F, so outside USDA zones 9-11 it must be overwintered under glass or replaced annually - a real commitment in cool-temperate gardens.

A clump-forming native milkweed with bright orange summer flowers, strong pollinator value, and tolerance for dry sunny sites.

Campanula carpatica is a low, mounding herbaceous perennial native to the rocky subalpine habitats of the Carpathian Mountains, ranging across Poland, the Czech Republic, Slovakia, Romania, and Ukraine (Wikipedia). Its wide, upward-facing bell flowers in violet-blue, white, or pink appear from June through August, making it one of the longest-blooming edging perennials available, and it holds an RHS Award of Garden Merit. The honest catch is longevity: it tends to behave as a short-lived perennial, often thinning or declining after a few seasons, so gardeners should plan for regular division or fresh plants from seed to hold the planting.

A tough, aromatic garden hybrid (Nepeta racemosa x N. nepetella) that forms a low, spreading mound of scalloped gray-green leaves topped by raceme-like spikes of two-lipped lavender-blue flowers from late spring into fall. Sterile and clump-forming rather than weedy, it shrugs off heat, drought, and deer, draws bees all season, and is mildly attractive to cats - a workhorse for border fronts, edging, and dry sunny sites.