Protea cynaroides f. white.
From Southern Africa, Protea cynaroides, The Giant Protea is the easiest species to recognise.
It has the largest flower heads of all proteas.
They are woody shrub 0.5 to 1.5 (2) m high.
One of the characteristic features is the presence of lignotubers.
These thickened woody areas on rhizomes (underground stems) have nodes that can produce new stems.
Shrubs have 1 (or more) thick erect stems that typically do not branch.
The leaves have a long petiole up to nearly 20 cm.
The smooth blades are round, elliptic or diamond-shaped.
Heads begin as an inverted cone then open up to a wide ‘V’ shaped bowl.
When fully open they can be up to 30 cm across the bract tips.
There are up to 10 series of involucral bracts around the flowers.
The outer bracts at the base are up to 12 cm long.
The narrow inner ones can be 15 to 30 cm long.
Bracts on a young head are white but the upper ones develop some pink externally.
The outer surface usually has short soft velvety hairs.
The shiny inner surface is a bright red.
The densely packed flowers are up to 10 cm long.
Of the 4 tepals that form a tube 1 is shorter than the others.
The straight tubes expand slightly near the top where the anthers are inserted.
Above the anther each tube has an appendage up to 3.5 cm long.
The curved appendages have dense long white hairs.
There are hairs on the inner surface of the tube.
The 4 anthers, with almost no free filament open into the tube through long slits.
The 5 mm ovary, with 1 ovule, has 1.5 cm long white hairs that become black.
The straight style around 6 to 8 cm long has short hairs at the base.
Near the end of the style is the up to 1.5 cm long pollen presenter.
This is linear and has longitudinal ridges.
The style immediately below the pollen presenter has a kink.
Forms and cultivars.
Protea cynaroides is a very variable plant in all its features.
Up to 80 variants have been described in South Africa.
A number of these, or their cultivars are sold as cut flowers or garden plants.
The White form, Protea cynaroides f. white is sold as ‘King White’.
It has bracts that are pale cream on both surfaces.
Other cultivars include a dwarf form under 35 cm high.
Leaves can have a yellow or red edge.
Bracts can be cream, yellow, pale to deep pink or crimson.
They can be red with a white edge and smooth to densely hairy.
J.F.
