Flower colour changes from white or yellow to various shades of red at or near the sites of harvestable pollen in Calytrix glutinosa, Grevillea pilulifera, Isopogon dubius and Petrophile biloba, and over most of the flower in Hypocalymma angustifolium, Verticordia chrysantha and V. huegelii and over the pseudanthium in Darwinia citriodora. All bee, wasp, beetle, fly, butterfly and moth visitors select flowers in the white/yellow phase rather than the red or intermediate phase. Nectar is produced by five species, harvestable pollen by four species and detectable perfume by three species, all of which features are usually absent from the red phase. The timing of the colour change in all species also corresponds to loss of stigma receptivity, completion of pollination and onset of ovule seed) swelling. Six species also undergo minor morphometric changes which discourage visitation. In all species, colour change is non-inducible by pollinators, taking 2–30 days to complete. In three protandrous species, all available pollen may be removed in the first visit, requiring transport of non-self pollen to rewardless flowers during the 10 h period of the yellow phase. These species are highly floriferous and occur in dense patches. Since only a small proportion of flowers may be receptive at any one time, it is concluded that retention of flower parts essentially serves to enhance long-distance attraction, while colour change maximizes pollination and foraging efficiency.