I have several Combrerum vines of various species; coccineum, microphyllum, fruticosum, rotundifolium, grandiflorum. Several are huge, in 20-25 gal pots, and none will bloom. All seem happy, growing well, but not a bud to be seen. Can anyone that has any of these tell me what conditions they were growing in when they flowered? Can't figure out what I am missing.