upright. An open inflorescence usually contains functionally male and female flowers at any one time. Inflorescences range from 6–15 cm in diameter with a basal ring of coloured bracts. Flowering processes Before a flower can be produced the plant must undergo floral induction and initiation. Floral induction involves physiological processes in the plant that result in the shoot apical meristem becoming competent to develop flowers. It involves biochemical changes at the apex, particularly those caused by cytokinins and the processes can be reversed. Floral initiation is the morphological transformation of an induced growing point from a vegetative to a floral primordium and involves the plant hormone florigen. Florigen is produced in the leaves in reproductively favourable conditions and acts in buds and growing tips to induce a number of different physiological and morphological changes. Once this process begins, in most plants, it cannot be reversed and the stems develop flowers, even if the initial start of the flower formation event was dependent of some environmental cue. Once the process begins, even if that cue is removed the stem will continue to develop a flower. Flower induction and initiation can simply occur when a plant has reached a mature enough age. However, in many plant species floral process occur in response to a number of environmental signals, or alternatively, are repressed by environmental signals. Floral initiation in T. speciosissima has been observed from mid-December, with floral buds developing more rapidly on older shoots and floral primordia emerging from mid-January to February. The floral primordia initiate over a 6–8 week period after primary flush growth from November to January. After the primordia initiation there may be another vegetative flush of growth on the plants. The flower develops in bud form for seven to eight months. The date of flowering is highly variable as waratah flowering is sensitive to its environment. Flowering tends to vary with geographic location and climatic differences, occurring from early August in coastal Queensland and up to December in Tasmania. Waratahs have a short flowering period in one location, although varieties can be selected to ensure a reasonable spread. It has been shown that in a population of 1000 seedlings where the total flowering time was five weeks, the spread was so that 10% flowered in week one and 10% in week five. Much variation was accounted for by varietal differences with plants of the one variety flowering at