Nerium oleander – Oleander is a common sight at tropical resorts, but it also makes a fine seasonal addition to summer gardens in temperate climates. It is best grown as a container specimen and moved outdoors in early summer as the night temperatures increase. Flower colours range from white, pink, red, yellow and salmon, with many being fragrant. All parts of this plant are poisonous. Hardy to zone 9-10.
Tibouchina urvilleana – Princess Flower is a native of Brazil with soft hairy foliage and 3″ to 5″ wide deep purple blooms produced from late spring through to autumn. This evergreen shrub can be trained into a small tree or standard and is best pruned in early spring and pinched occasionally to increase density. Overwinter indoors and water sparingly at this time. Hardy to zone 10.
Mandevilla (syn. Dipladenia) This South American native bears large tubular flowers, ranging in colour from white, pink, red and yellow. Many gardeners still differentiate Mandevilla by its vining habit, larger (slightly rough) leaves and flowers, versus the smaller blooms and glossier foliage of Dipladenia. Given its climbing nature, Mandevilla is bets grown in a large container with a mini-trellis so it can be brought in for winter. Hardy to zone 9-10.
Solanum laciniatum (closely related to Solanum aviculare) – Commonly known as Kangaroo Apple, this member of the Potato family is an evergreen shrub that can easily be pruned into a small standard. The spring through summer flowers are violet-blue and are followed by poisonous green fruits, that ripen to orange. These are short-lived shrubs, so replace with seed-grown plants or semi-ripe cuttings in summer to early fall. Hardy to zone 10-11.
Bougainvillea – A large group of evergreen shrubs and climbers derived from several species (glabra, peruviana, spectabilis) and hybrids. A few common cultivars include ‘Scarlet O’Hara’ (shown), ‘Raspberry Ice’ (variegated) and ‘Barbara Karst’ (red). They produce colourful bracts starting from early summer and greatly dislike root disturbance, so they are best grown in containers. Hardy to zone 9-10.