Lily of the valley

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.

Common lungwort is a low-growing, rhizomatous herbaceous perennial native to deciduous and beech-mixed woodlands of central and western Europe, from Belgium and the Netherlands east to the Caucasus (Wikipedia). Its white-spotted, heart-shaped leaves and early-spring flowers - opening pink then aging to blue-purple as petal pH shifts - make it one of the first-blooming shade groundcovers in the garden. It thrives beneath deciduous trees in humus-rich, consistently moist soil and is reliably hardy through zone 3. The honest catch: in heat, drought, or poor air circulation it collapses into disfiguring powdery mildew mid-summer, often leaving the foliage blackened and unsightly until new basal growth re-emerges - siting in cool, evenly moist shade with good airflow is not optional.

Common periwinkle is a trailing, mat-forming evergreen subshrub native to central and southern Europe - from Portugal and France east to the Caucasus and Turkey - grown worldwide as a tough groundcover for its violet-blue spring flowers and glossy dark leaves. It thrives in shade and dry conditions where little else will grow, and establishes quickly. The honest catch is its invasive potential outside its native range: in North America it escapes cultivation readily, forms dense clonal mats that exclude native wildflowers, and - once established - is very difficult to eradicate; all parts are also toxic if ingested.

Bergenia cordifolia (often treated by botanists as a synonym within B. crassifolia) is a tough, evergreen perennial native to the Altai Mountains, southern Siberia and Mongolia, grown for its bold, heart-shaped leathery leaves that flush red-bronze through winter and its deep pink flower spikes in early-to-mid spring. It is one of the most tolerant groundcovers in cultivation - enduring deep shade, poor soil, drought, and hard continental cold (commonly rated to USDA Zone 3 in US horticulture; RHS rates it H7, hardy below -4°F). The honest catch is its shallowly creeping rhizomes: in mild, moist climates they can colonise well beyond the intended planting, and the large, persistent leaves trap fallen debris and are notoriously attractive to slugs and vine weevils.

A bulbous spring perennial native to the deciduous woodlands and hedgerows of western Atlantic Europe - Great Britain, Ireland, France, and the Iberian Peninsula - where it carpets ancient woodland floors in violet-blue before the tree canopy closes. In gardens it naturalizes into fragrant, nodding-raceme colonies under deciduous trees and is one of the most evocative harbingers of a British spring. The honest catch is twofold: all parts of the plant (especially the bulbs) are toxic, and it hybridizes freely with the Spanish bluebell (H. hispanica), producing fertile intermediates that are gradually displacing the pure native in the wild - so gardeners should not plant the two species near each other.

A shade-tolerant hosta with glossy foliage and fragrant white late-summer flowers for paths, containers, and woodland edges.