Skip to content
3 May 2021

Must-See Plants this May in the Garden

This May we feature flowers, bark, fleshy scales and giant flower spikes. All botanic bases are covered by this month's Must See plants. See the full map for the plant locations here.

Plum or Illawarra Pine - Podocarpus elatus

This southern hemisphere conifer is endemic to northern NSW and Queensland and is one of 95 species of Podocarps. Unlike other conifers, the Podocarps do not have seed cones, instead they have a single seed attached by a fleshy receptacle to the branch. The seed is hard and inedible, but the purple black fleshy receptacle underneath is edible and eaten by Aboriginal people. Male trees produce drooping cones that release their pollen to be spread by the wind. 

Vireya Rhododendrons

Vireya Rhododendrons, known as Tropical Rhododenrons are native to tropical SE Asia from Burma to Northern Australia, with many species occuring in Papua New Guinea. They mostly grow in cool mountainous areas as epiphytes in the cloud forest. Many cultivars are available that produce bunches of glorious flowers in a range of colours. Australia has one species, Rhododendron lochiae that grows above 950m in the Wet Tropics World Heritage area in north Queensland. Rhododendron 'Fire Plum' pictured below.

Native Hoya or Wax Flower - Hoya australis

This twining vine can be found in dry rainforest, coastal bluffs and littoral rainforest from Cooktown in northern Queensland to Grafton in NSW. The flowers can appear any time of year and are clustered on top of a long peduncle. Each flower has five thick white waxy triangular petals with red markings at the centre. The flowers have a strong scent and produce abundant nectar. They are pollinated by the Southern Grass-Dart Butterfly. A great plant for hanging baskets, available at the Growing Friends Nursery

Stringybark She-Oak - Allocasuarina inophloia

What wonderful hairy bark! She-Oaks are best known for their foliage, but this one is distinguished by its unusual bark. Like all She-Oaks, it has segmented branchlets that look like pine needles, each segment known as an article, 4 -6 mm long. The leaves are reduced to tiny scales between them. Individual plants are either male and female, the females produce small red flowers in winter followed by woody fruit. The bark provides great nesting material for many birds.

Mexican Sage - Salvia leucantha 'Velour Pink'

This Salvia is a native to subtropical and tropical conifer forests of central and eastern Mexico. The word Salvia comes from the Latin word salveo meaning to heal, referring to the curative properties of some members of the genus. Salvia is the largest genus in the mint family (Lamiaceae) and includes Sage (Salvia officinalis). This Mexican sage is prized for its late season, bee attracting flowers. Look out for other cultivars of the this species with bright purple or white flowers.

Giant or Pulque Agave - Agave salmiana

We are lucky to be witnessing a once in a lifetime event for this Agave. It is in the process of flowering, after sixteen years growing in this Garden. The flower spike emerges from a rosette of thick succulent leaves with sharp hooks on the margins and a rigid terminal spine. The flower spike branches as it rises with yellow flowers at the ends, looking like a giant candelarbra. The spike is impressively high, but after flowering the plant will die, a process called monocarpism.

Angel's Trumpet - Brugmansia cultivars

Angel’s Trumpets are native to tropical South America, but all seven species are extinct in the wild. They have survived due to cultivation by indigenous people for medicinal and religious purposes and for ornamental use. The flowers are large, fragrant and pendulous with many different forms and colours. This cultivar has double pink flowers, but you can see white single and double flower varieties elsewhere in the garden. A member of the Solanaceae family, all parts of the plant are poisonous. 

Happy Tree - Camptotheca acuminata

This deciduous tree from China was used in traditional medicine to cure stubborn phlegm and other diseases, making patients happy. An alkaloid, camptothecan was isolated from the bark and stems in the 1950s that showed anti-cancer properties. Camptothecan was too toxic for use, but two derivatives were synthesised, one approved for cancer treatment in 1996, the other in 2007. In Autumn, look for the fruits that look a bit like wild bananas clustered in a ball that fall to the ground when ripe.

Learn more

Join a Guided Walk of the Garden with one of our knowledgeable Volunteer Guides on Thursday, Friday, Saturday or Sunday. Find out more here (availability may be temporary unavailable at times due to COVID-19 restrictions).

If you are a journalist and have a media enquiry about this story, please click here for contact details and more information.