CULTIVATION OF THE PINK MULLA MULLA, PTILOTUS-EXALTATUS NEES .2. NUTRITION AND GROWTH-REGULATION

Ptilotus exaltatus Nees. has the potential to be marketed as a flowering pot plant if conditions for rapid growth can be combined with growth regulator application to produce a compact plant. Slow release fertilizer (6 kg m-3 Osmocote) in the medium plus supplementary liquid application of nitrogen promoted plant growth and early flowering with no effect on flower stem number. Drenching with chlormequat at 100 or 250 mg active ingredient per 150 mm pot reduced stem length by 50% with no effect on the number or size of inflorescences. Higher rates were phytotoxic. Paclobutrazol reduced stem length but resulted in a less attractive plant form.