Frankenia pauciflora, sea heath, (native of Western Australia) is a prostrate or rounded perennial shrub to 0.5 metres with many branches often forming mats. The small linear and somewhat fleshy, dull green leaves are arranged oppostively with backward curving margins and are 3-7mm long and 1mm wide. Flowers are pink or white and stalkless. The 5-6 petals are 9-12mm long and the fruit are capsules which contain several smooth warty seeds.
Eastern Australian populations are generally referred to as var. gunnii.
I could only find one plant for "F" so have shown lots of lovely photographs to make up for that.