Japanese forest grass

Farfugium japonicum is an evergreen rhizomatous perennial native to streamsides and rocky seashores of Japan, Korea, Taiwan, and coastal China, where it is known as tsuwabuki (石蘗). In gardens it delivers bold, kidney-shaped leaves up to 10 inches across and cheerful yellow daisy flowers in autumn and winter - a genuinely useful combination for dark, damp corners. The honest catch is toxicity: the plant contains petasitenine, a carcinogenic pyrrolizidine alkaloid; it must be kept out of reach of children and pets and handled with care, and it is frost-tender above USDA zone 7b, dying back or suffering severe leaf scorch in hard freezes.

Persian buttercup is a tuberous herbaceous perennial native to the eastern Mediterranean - from Cyprus, Crete, and Turkey across to Iran, Iraq, and the Levant - where it blooms in rocky scrub and meadows in late winter through spring. In gardens it is prized for its luminous, poppy-like flowers in red, orange, pink, yellow, and white (wild single forms) or the dense, multi-layered doubles of commercial 'Tecolote' and 'Bloomingdale' strains beloved by florists. The honest catch is its frost-tenderness: the tubers are killed below roughly 14°F, so gardeners in USDA zones 7 and colder must lift and store them after foliage dies down each summer, and the whole plant contains protoanemonin, a skin and gut irritant toxic to humans and livestock on contact or ingestion.

Gentiana acaulis is a low, mat-forming alpine perennial native to the mountains of central and southern Europe - the Alps, Pyrenees, and Balkans - where it grows in short turf and rocky meadows from 2,625 to 9,843 feet elevation. In gardens it is prized for its astonishing, deep-blue trumpet flowers in late spring, and it has received the RHS Award of Garden Merit. The honest catch is its notorious habit of "sulking": well-established plants can refuse to flower for years with no apparent cause, and the gardener's only remedy is to dig and replant the mat a few inches away - a maddening behaviour that makes it a reliable showpiece in some gardens and a frustrating non-bloomer in others.

Hippeastrum x hybridum is a complex garden hybrid derived from six or more wild Hippeastrum species native to tropical and subtropical South America, developed through intensive breeding since the late 18th century and now the dominant "amaryllis" sold worldwide as a holiday bulb. It produces spectacular trumpet-shaped flowers - 5 to 8 inches across - on stout leafless scapes in red, pink, white, orange, salmon, or bicolour, making it one of the most dramatic winter-flowering houseplants available. The honest catch is toxicity: the entire plant, especially the bulb, contains lycorine and related alkaloids at concentrations that cause vomiting, salivation, tremors, and hypotension in pets and children, so it must be placed out of reach and handled with care.

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.

Veltheimia bracteata, the forest lily, is a winter-growing bulbous perennial from the forest margins and coastal scrub of South Africa's Eastern Cape, grown for its glossy rosette of wavy-edged strap leaves and a tall, dense raceme of pendent tubular flowers in shades of pink to rose, blooming in late winter through spring when little else is in flower. It is frost-tender (RHS H2): it tolerates cool conditions but not freezing, so outside roughly USDA zone 9b-11 it is grown as a container or conservatory bulb, dormant and dry through summer. It thrives in semi-shade with humus-rich, well-drained soil and makes an excellent pot specimen. The bird-pollinated flowers attract sunbirds. As a member of Asparagaceae (subfamily Scilloideae), it is grown for ornament only; the bulb is toxic and must not be eaten. It is well-behaved and not reported as invasive.