Propagation
Fresh seed should be sown in a well-drained media and keep moist but not wet. Maintain a temperature of 18º to 21º C. (64º to 75º F) in an unheated glasshouse or open frame. Germination occurs within 3-weeks to 3-months depending on the species, then prick-out and pot up.
Careful not to over water seedlings, as they are prone to damping off and larger plants are difficult to transplant.
When removing seed from Banksia fruits it may be necessary to place the fruit in an oven for 60 minutes at a temperature of 120° C. to simulating the effect of a bushfire to opening the valves.
General pruning information
When pruning reduce only the new growth as cutting old wood is likely to cause dieback. Limbs may be removed back to the collar.
This plant re-shoots after low intensity fire.
Botanic information
Leaf: The leaves are elliptical to obovate and up to 40mm (1½in) wide with a slightly undulating margin. The upper surface is rough becoming glabrous and the underside is covered in white tomentose with a reddish mid rib.
Flower: The inflorescence is a cylindrical spike up to 190mm (7½in) long containing golden tubulate flowers with a pale-yellow style that is up to 26 mm (1 in) long. It is pinkish-brown in bud and yellow at maturity with the spent inflorescence persistent on the shrub for many years. They appear from autumn to early winter.
Fruit: The follicles are narrow elliptical with smooth glabrous valves that are semi-elliptical. These normally remain closed until burnt. The obovate winged seeds are 16mm (µin) long.
Cultivation
Generally, Banksia species prefer a well drained, sandy soil that is tending acidic but many species from Western Australia grow on acidic top soils with alkaline subsoil. When the growing Western Australian species outside their native habitat technique of building a garden bed, of acidic soil above a layer of agricultural lime commonly produces better results particularly in raised garden beds or on slopes. During establishment, keep the soil moist but not wet and do not use fertiliser that contains phosphorus.