Frangipanis grow well in warm coastal gardens and even inland with frost protection. Although the frangipani is widely associated with tropical islands such as Hawaii, they actually originated in Central America, Mexico and Venezuela, but have since spread around the tropics and subtropics.
The most common frangipani is Plumeria rubra var. acutifolia. It has single white propeller-shaped flowers with a bright yellow centre and a strong perfume. There are many named and unnamed varieties with yellow, pink, red, dark red, violet and sunset-toned flowers, as well as dwarf and semi-dwarf varieties that are ideal outdoor plants for small gardens, courtyards or containers.
Temperatures as well as growing conditions influence the intensity of flower colour in frangipanis. Those grown in full sun and in tropical climates will have the most intensely-coloured blooms, but they are all equally rewarding wherever they are grown!
Frangipani planting & care
Treat frangipanis as large succulents. They grow as deciduous trees that can reach 8m high and wide producing their best flowers from late spring to autumn in warm sunny positions. These plants are salt, drought and heat tolerant, so they are an ideal addition to many gardens.
Frost and cold can damage shoots and branch tips, leading to dieback and fungal disease. In areas which are not usually affected by frost, remember to cover frangipanis at night if frost is forecast. In cold winter zones, plant frangipanis in a warm microclimate such as beside a north-facing masonry wall or in a large container that can you can move into a sheltered spot over winter.
As well as growing frangipanis in warm, sheltered spots, they need well-drained soil. In areas with heavy clay or poorly-drained soil, grow frangipanis in raised beds or large containers. Use a good quality potting mix in containers.
These trees don’t need lots of water or fertiliser, but grow and flower better with an application of all-purpose fertiliser in spring as growth resumes. You can surround your frangipanis with organic or gravel mulch, but don’t let mulch build up around the trunk, as this can lead to rots.
Frangipanis don’t need to be pruned, except to remove wayward, damaged or cold-affected branches. Cutting back to a node can create a more bushy shape. Poor pruning can disfigure the tree and is very obvious in winter when the tree is bare. Cut damaged branches back to a main branch for a clean look.
Frangipani pests & diseases
Until recently, there was little that could go wrong with a frangipani. The many mature trees that grow in old gardens are testament to the longevity of frangipanis.
Some 25 years ago, frangipani rust was accidentally introduced into Australia and is now present in all areas. This fungal disease attacks frangipani leaves and is prevalent in late summer and early autumn. Orange to brown rusty pustules appear on the underside of the leaves. The leaves die back and fall. Badly affected plants can be defoliated and may have poor flowering.
Practice good hygiene by picking off affected leaves as soon as they are identified and collecting and disposing of all fallen leaves. There are many fungicides registered for frangipani rust including copper- or potassium-based and all-purpose rose fungicides. Apply when the infection is first seen, and also as a protective spray for new foliage re-growing after the mature leaves have been dropped to due infection.
As well as spraying while the tree is in leaf, overwintering of spores may be reduced by applying a winter spray of lime sulphur while the tree is completely dormant. Also, gather up old leaves lying under the tree. Dispose of these in a bag in the garbage (not compost). As rust spreads by spores, encourage neighbours to also treat their frangipanis.