I remember seeing and collecting the tuberous roots of this species years ago in Gaborone, Botswana, where it is a very common plant. The bright yellow flowers open in the sunshine, and the hard brown tuberous root is tough enough to sit dormant out of the ground for months. In fact that's what the root of this particular plant is doing right now, sitting on a table in my classroom. I planted it out in the slope garden last summer, and it grew several prostrate branches which bore yellow flowers and made quite a few seeds, despite a rainy summer quite unlike its preferred hot and sunny summer growing season in Africa. Seeds may take their time coming up, I suspect some kind of weird dormancy requirement, yet when I grew them at NYBG they sometimes self sowed in their neigbor's pots. Talinum caffrum is easy to grow and attractive enough to deserve a sunny garden spot for the summer, but it is definitely a plant geek's plant, and not something the neighbor, or the nursery down the road, is likely to have.