Thanks for this post Surajit ji! Persicaria limbata from me too. Ochrea with a spreading limb are visible in the fourth photograph.
These links will also help. Kew<http://apps.kew.org/efloras/namedetail.do?flora=fz&taxon=11687&nameid=29972> Flora of Zimbabwe<http://66.39.29.198/speciesdata/image-display.php?species_id=121830&image_id=2> Best regards, Ritesh. --
