Glory of the Snow

A low, mat-forming member of the mustard family from the Mediterranean coast, grown almost everywhere as a cool-season annual for its dense mounds of tiny, sweetly fragrant white four-petaled flowers. The flowering is so profuse it often hides the gray-green foliage entirely. It thrives in cool weather, tolerates dry soil and drought, and is a reliable nectar source for small pollinators.

Heather, or ling (Calluna vulgaris), is the low, wiry evergreen shrub that colours the moors and heaths of Europe purple in late summer. It grows only 4 inches to 24 inches tall in dense, spreading mats of tiny scale-like leaves, and from July to September it is covered in spikes of mauve (wild) to white, pink, or red (cultivar) flowers that draw an intense traffic of bees - the source of prized heather honey. It is beautiful, wildlife-rich, and extremely cold-hardy, but it is also a fussy plant with two non-negotiable demands: genuinely acidic soil and cool summers. The honest catches: it will not thrive on chalk or in hot, humid heat (NC State advises against planting south of zone 6), and where introduced - notably New Zealand - it has become an invasive weed.

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.

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.

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.

Cheddar pink is a low, mat-forming evergreen perennial pink (a Dianthus, not a true carnation) native to calcareous rock ledges and cliff faces across western and central Europe, from the protected population at Cheddar Gorge in England east to Ukraine. Its intensely clove-scented, fringed rose-pink flowers and blue-grey foliage make it one of the finest front-of-border edging plants in a sunny, sharply drained garden. The honest catch is drainage: in any soil that holds winter moisture the crown rots reliably, so it fails in heavy clay or irrigated beds and thrives only where drainage is sharp and the site stays dry underfoot in cold months.