Closeup of a macadamia flower. The flower cluster is a raceme with 200 or more flowers, that have no petals, but four petaloid sepals. Flowers are pink on M. tetraphylla and creamy white on M. integrifolia. Each flower has four stamens and a pistil with an ovary which contains two ovules. Nut development in macadamia from full flowering (anthesis) to kernel maturity takes about 30 weeks. Shallo.