Flowering right now for me is Clivia miniata 'Hirao', which is possibly the best green Clivia as of today. I bought 3 flowering-size plants in Japan last year. All 3 plants flowered for me within a month or so after I took them home. I have noticed that the flowers of each of the plants are slightly different from each other. I have noticed that the flowers of one of the plants are in fact slightly perfumed - I have to put my nose right to the flowers to feel the scent. There are suppliers who offer seed of named cultivars. However, the main problem with Clivia is seedlings are not always true to the colour of their parents. I was told that even the breeder of 'Hirao', Toshio Koike has got seedlings which turn out to be yellow or orange instead of green. To make sure what you want, Toshio Koike suggests that one must buy division or plants which have flowered before.
