Trident Maple

Amur maple (Acer ginnala, accepted by Kew's Plants of the World Online as Acer tataricum subsp. ginnala) is a small, fast-growing deciduous tree or large multi-stemmed shrub from northeastern Asia - the Russian Far East, northeastern China, and Korea. At 15 to 20 feet it fits where a full-size maple cannot, and it earns that place with three seasons of interest: fragrant greenish-yellow flowers in spring, which is an unusual scent for a maple and an early nectar source for bees; small glossy three-lobed leaves through summer; and reliable, often brilliant red-to-orange fall color that arrives early. It is also one of the hardiest maples, tolerant of cold, wind, dry soil, and a wide range of pH. The honest catch, and it is a serious one for North American gardeners, is that it self-sows prolifically and has escaped cultivation to become invasive across parts of the US Midwest and Northeast, where its shade-tolerant seedlings crowd native shrubs and understory trees in open woods, savannas, and prairies. Several states list it as invasive or a noxious weed. Check your local invasive-species list before planting, and be prepared to remove seedlings if you do.

Buddhist pine (Podocarpus macrophyllus) is a slow-growing evergreen conifer native to southern Japan, southern and eastern China, Taiwan, and northern Myanmar, long prized in East Asian gardens and feng shui traditions. In mild climates it makes a handsome, dense column of strap-like dark-green foliage suitable for hedging, topiary, or a statement specimen; it also tolerates container culture well. The honest catch is its frost-tenderness: plants are reliable only from zone 7b (about 10°F) southward, and a late cold snap in zone 7 can kill established specimens to the ground. Layered on that is its pace - growth is genuinely slow, so a screening hedge planted today may take 15-20 years to reach useful height.

Cordyline australis is a dramatic, palm-like evergreen tree native to New Zealand, where it ranges from North Cape to the southern South Island. In warm-temperate gardens (USDA zones 8-11) it makes an unmistakable structural focal point with its stout trunk, arching sword-leaf crown, and spectacular fragrant flower panicles in late spring. The honest catch is its scale and tenderness: it can exceed 33 feet in mild climates, its fibrous roots are expansive and difficult to remove, a single hard frost below about 23°F can kill or badly damage an established specimen, and the saponin-bearing foliage is toxic to cats and dogs - making it a gamble outside sheltered coastal or urban sites in colder zone-8 gardens.

English yew (Taxus baccata) is a slow-growing, exceptionally long-lived evergreen conifer native across Europe (except Iceland), the Caucasus, Turkey eastward to northern Iran, and Morocco and Algeria in North Africa, valued for centuries as the definitive topiary and formal hedge tree. Its dense, dark-green needle foliage tolerates extreme shade and hard clipping, making it the premier structural plant for sculptured gardens. The honest catch is severe toxicity: nearly every part of the plant - needles, bark, seeds - contains cardiotoxic taxine alkaloids with no antidote, posing a lethal risk to humans, livestock, horses, and dogs; only the red fleshy aril is non-toxic, though the enclosed seed is deadly.

Brazilian jasmine is an evergreen, woody twining vine endemic to the state of Rio de Janeiro in southeastern Brazil, and one of the species from which many of the garden mandevilla hybrids sold for patios, porches, and hanging baskets have been developed. Despite the name it is not a true jasmine: it belongs to the dogbane family (Apocynaceae), and its flowers are funnel-shaped trumpets 2 to 3 inches across, pink-red in the species and red, pink, white, or cream in its many cultivars, carried over a long season from spring into autumn. Its leaves are thick, leathery, and glossy dark green, to about 2 inches long, and it builds large starchy tuberous roots that help it ride out dry spells. It was first described as Dipladenia sanderi, and its garden forms are still generally sold as 'Dipladenia'. It is frost-tender: a frost kills it, so it lives outdoors year-round only in USDA zones 10a-11b, the range published for mandevillas, and is grown as a summer annual or an overwintered container plant everywhere colder. Its milky sap irritates skin and may be toxic if swallowed.

Frangipani (also called plumeria, temple tree, or nosegay) is a small, rounded, deciduous tree from the dry, hot regions of Mexico and Central America south to Colombia and Venezuela, now planted throughout the tropics for its intensely fragrant flowers. Thick, blunt, grey-barked branches carry large leaves clustered at their tips, and from late spring to fall each branch tip ends in a cluster of five-petaled flowers, pink to red in the species, while garden forms run to white, yellow, and bicolors. In a frost-free garden it reaches 15 to 25 feet tall and wide. It is frost-tender and grows in the ground only in USDA zones 10b-12b; UF/IFAS warns that plumerias can be susceptible to cold damage, so anywhere colder it is grown in a container and wintered indoors. Broken branches bleed a milky sap that irritates skin and eyes, and the RHS lists the plant as harmful if eaten, for people and pets alike; UF/IFAS adds that plumerias are not particularly poisonous compared with other landscape plants such as oleander. It is the national flower of Nicaragua, where it is called sacuanjoche. Wikipedia reports it naturalized in most parts of tropical Asia and the Pacific Islands, but the Pacific Island Ecosystems at Risk weed risk assessment found no evidence of naturalization and rates it low risk.