I'm still with Kleinia petraea, the leaves shoot upwards from the stems where leaves on Portulaca oleracea tend to lay down more, the leaves on the latter also look more green than bluish with purple tints. P. oleracea shows stems branching from the main stems too, I can't see that on this plant.
The flower stem which can be seen at the lower left of the firs pic has a dead flower on it, not yet made seed, the flower stems on K. petraea are long.
http://www.wnmu.edu/academic/n...
http://www.zimbabweflora.co.zw...
