The Pacific Bulb Society says this:
"Crinum bulbispermum is native to South Africa. It has distinctive long, tapered glaucous foliage and blooms early in the season, but often repeats later. The flowers are typically white with reddish keels, but there is much variation in the coverage and intensity of anthocyanins pigmentation. Variations from white forms, free of anthocyanins & with green keels, to nearly red heavily pigmented forms exist. It is also common for there to be forms which open quite pale & get progressively more pigmented over a period of days with the darkening rose-red pigment spreading typically from the keels outward across the tepal and varying in a range of expression from individual to individual with some getting quite dark rose red all over to others which only darken near the keels. This characteristic also seems to be affected by the temperature with flowers on the same plant deepening in tone & pigmentation more rapidly & intensely with blooms occurring during hot temperatures compared to those that occur during cool parts of the season. This characteristic is expressed in several hybrids as well. This Crinum species is among the most tolerant of cold winter temperatures and may be the most cold tolerant Crinum species. There are naturalized colonies and scattered populations of this species across the southeastern United States and though it may be locally common in some areas, its occurrences are variable in many parts of the region. Within these populations, sometimes unique forms can be found though usually they are less than distinct."