Wormwood

A tall, sun-loving, drought-tolerant perennial in the daisy family, grown for its broad, flat-topped corymbs of tiny golden-yellow flowers held on stiff stems above finely divided, aromatic gray-green ferny foliage. Native to the Caucasus, Iran, and Afghanistan and long naturalized in gardens worldwide, it forms a tidy upright clump (rather than running like common yarrow) and is one of the most reliable, low-care pollinator and cut-flower plants for hot, dry, full-sun borders.

An airy, see-through ornamental in the vervain family (Verbenaceae), native to South America and naturalized across the warm southeastern United States. NC State Extension describes an erect plant 2 to 5 feet tall on thin but strong red-marked green stems, topped from summer into fall by dense, flat-topped clusters of small tubular purple-lavender flowers held well above mostly basal, lance-shaped, serrated dark-green leaves. A perennial in USDA zones 7-11 (grown as an annual in colder climates), it is fast-growing, drought and deer tolerant, and a magnet for bees, butterflies, and hummingbirds - though it self-sows freely and some sources have labeled it invasive.

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.

Liriope muscari is an evergreen, grass-like perennial native to the shady forest understories of China, Japan, and Korea, where it grows at elevations of 330 to 4,600 feet. In gardens it forms dense, weed-suppressing clumps of arching dark-green foliage topped by spikes of lilac-purple flowers in late summer, followed by ornamental black berries - earning it the RHS Award of Garden Merit. It is drought-tolerant and remarkably adaptable, but the honest catch is its behaviour outside its native range: in parts of the eastern United States it is a documented invasive species, spreading by rhizomes and self-seeding into natural areas, and it provides minimal wildlife value compared with native groundcover alternatives.

Cotton lavender is a compact, mound-forming evergreen shrub native to the western and central Mediterranean, valued for its intensely silver-grey, aromatic feathery foliage and bright yellow button flowers in summer. In the garden it excels as a low edging, silver accent, or knot-garden structural element and tolerates drought and poor soils with ease once established. The honest catch is its short life in heavy or wet ground: without sharp drainage and a hard annual clip it becomes woody, open-centred, and collapses within three to five years, making site selection the single most important decision before planting.

Creeping cotoneaster is a deciduous spreading shrub native to the mountains of central and southwestern China, Nepal, and Taiwan, prized for its distinctive flat herringbone branching, tiny pink-white summer flowers, and masses of vivid red autumn berries that sustain birds through winter. It holds the RHS Award of Garden Merit and tolerates poor, dry soils on banks and walls where little else will perform. The honest catch is twofold: the berries are mildly toxic to humans and pets (cyanogenic seeds, GI-irritant flesh), and the plant self-seeds freely enough that it is naturalising widely in the UK and Ireland and is considered potentially invasive - a real concern before planting near wild margins or hedgerows.