A vigorous, scrambling, semi-climbing tender shrub that flowers almost without pause through the warm months, carrying broad clusters of soft sky-blue (or, in the white form, pure white) phlox-like flowers. Known as the Cape plumbago or Cape leadwort, it is native to South Africa (POWO, Kew) and is grown worldwide as an easy, long-flowering ornamental. The honest catch is its frost-tenderness: it is hardy only in USDA zones 9a-11, so in cold climates it is grown as a conservatory or large-container plant, or treated as a summer annual. Left to its own devices it climbs or sprawls 6 to 10 feet and needs support, or hard pruning, to keep its shape; the flower calyces are sticky and glandular and cling to clothing and animal fur (its own seed-dispersal trick), and it suckers. In return it is one of the best blue-flowered butterfly plants for a warm garden.

A bushy, semi-evergreen small shrub (subshrub) grown for an exceptionally long succession of two-lipped flowers — classically bright red or magenta-pink, with many named cultivars such as the bicolour 'Hot Lips' — borne from early summer right up to the first frosts. Its small aromatic leaves are often said to smell of blackcurrant when crushed. One of the very best garden plants for pollinators in a hot, dry, sunny spot, it is tough and free-flowering but only borderline hardy (RHS H4): in cold-winter climates it needs a warm, sheltered position and sharp drainage and is often grown as a tender perennial. It is an ORNAMENTAL salvia and is NOT the culinary sage (that is Salvia officinalis) — it is grown for flowers and pollinators, not for food.

An evergreen western-Mediterranean rockrose for the hottest, driest, leanest corner of a full-sun garden. Soft grey-felted foliage carries large, papery, crumpled pink flowers through spring and early summer, each open for a single day. Built for drought and poor soil, it is short-lived and resents wet, cold, or rich ground — a plant to site hard and never to pamper.

Jerusalem sage (Phlomis fruticosa) is an evergreen Mediterranean shrub grown for its bold foliage and its distinctive tiered flowers. Through spring and into early summer the stems carry whorl upon whorl of hooded, butter-yellow blooms stacked in neat tiers up the stem, set against sage-like, wrinkled, grey-green leaves that are softly felted with hairs. Despite the name it is not a true sage and is not culinary — it is grown purely as an ornamental. It is a tough, sun-loving, drought-tolerant shrub for hot, dry, sharply-drained places: gravel gardens, Mediterranean-style borders, and hot sunny banks. The honest caveat is that it resents wet, heavy soil and cold winters; it is only borderline hardy (RHS H4), so in cold-winter areas it needs a warm, sheltered spot and very sharp drainage to come through. Trim it lightly after flowering to keep it bushy and compact, leave the dried seedheads for winter structure, and enjoy it as the good bee plant it is.

A frost-tender broadleaf shrub from tropical America grown across most of North America as a heat- and drought-tough annual bedding plant, container subject, or houseplant. Dense 2-inch hemispherical clusters of tiny five-lobed flowers — often white, yellow, orange, red, and purple mixed in the same head — bloom July to frost and draw hummingbirds and butterflies. The rough, aromatic foliage and every other part are toxic if eaten, and the species has escaped cultivation to become invasive along the warm-winter southern US coast.

A tough, fine-textured warm-season bunchgrass of the North American shortgrass prairie, named for its distinctive seed spikes that hang from one side of the arching stem like a comb or an eyebrow. Bluish-gray summer foliage forms dense low clumps that turn golden brown — sometimes orange and red — in autumn, while reddish-purple flowers rise above on slender culms in summer. Exceptionally drought- and heat-tolerant once established, it is a larval host for several prairie skipper butterflies and a seed source for granivorous birds.