Silver tree family
The silver tree family or Proteus family (Proteaceae) is a family rich in species. It includes 77 genera with about 1,600 species. These are so diverse that family resemblances are often hard to recognize. All of them occur in the southern hemisphere, most of them in Australia and South Africa.
Silver trees (Leucadendron)
The genus of the silver trees or shimmer trees can only be found at the southern tip of Africa (Cape Floristic Region). Leucadendron approximately comprises 95 species.
The genus owes its name to the true silver tree (Leucadendron argenteum) with its white hairy, silvery shimmering leaves.
All Leucadendron species are highly threatened and are on the Red List of endangered plant species. Two species are already extinct. Other endangered species have been taken into conservation culture by various botanical gardens.
Banksia (Banksia)
The genus Banksia is native to Australia. It was named in honor of the British botanist Sir Joseph Banks, who accompanied Captain Cook on his first voyage around the world (1768-1771).
In summer several Banksia shrubs stand in huge tubs outside to the right and left of the entrance to the greenhouses. This is probably the largest specimen of Banksia serrata in Europe.
Rock-hard nuts develop from the inflorescences. The infructescence stays on the plant until its opening is stimulated by the next bushfire. This can take years or even decades. The nuts open in the heat of the fire, and the seeds fall into the soil, which is fertilized by the ash, ready to germinate.
Ecologists call such plants pyrophytes.
Banksia media grows up to 10 meters high. The cylindrical, fragrant, yellow flower heads, up to 20 cm long, attract the mouse-sized honey possums and the Honeyeater birds, as well as numerous insects.
The infructescence opened in the fire. Banksia serrata is pollinated by marsupials and parrots. Therefore, their yellow-green inflorescences must be very stable. They resemble toilet brushes in shape, structure and size.
Other Proteaceae species
Spider flower (Grevillea)
Grevillea banksii is native to Australia. It grows as a shrub or small tree and reaches heights of up to 7 meters. The genus Grevillea alone comprises about 360 species. Among them, only five are not native to Australia. They are evergreen.
Pincushion (Leucospermum)
The narrow stamens, which rise up like a pincushion, have inspired the plant´s name. The approximately 50 species are all native to southern Africa. Leucospermum erubescens blooms very abundantly and is very attractive.
Sugarbushes (Protea)
Proteas are also called Sugarbushes, "suikerbos" in Afrikaans. Proteas include about 115 species. They are native to southern Africa. Protea obtusifolia has dark green leaves and large wine-red flower heads.