I find that my clivia needs a rest period in the autumn to set flowering spikes. I put mine in the garage by a small window, where it experiences temps down towards freezing, and I withhold water. Then around Christmas, in it comes, blooming February - March. This year I didn't do this, and what do you know? No flowers for me! I'm growing it over on Long Island, NY, USA, so your might need to adjust accordingly.