Cymbidiums can withstand a wide variety of temps from near freezing to hot summer but mine in the UK have to live between 5C-34C. My understanding is that they require a drop in temp between day & night to initiate the flower spikes. Mine remain outside in the Autumn until the night temps reach approx 5C and that seems to be ok for them. I never let mine completely dry out but watering drops from 2-3 times a week in the height of summer to every 7-10 days in winter. Mine are potted in a bark mix.

There are now some modern hybrids that have been specifically bred to be �heat tolerant or warmth tolerant� and these do not require the same drop in temp. however they are nowhere near as available as the �normal� cyms. If you divide a cym it may well miss a year of flowering.

It is interesting that you can get 7 to flower as this would indicate that you do get the temp drop needed. Also some hybrids will miss a year between flowering, so these may well be OK. As these others do flower, and you are unlikely to have such a large portion of � heat tolerant� varieties in your collection, I just wonder if there is a specific problem with the ones that do not flower such as poor potting material, lack of light or lack of nutrients.

Hi
Thre used to be a nursery in florida(US) that specialized in heat tolerant Cyms.They were doing crosses between the two races to get the large flowers while not needing a cool down. You can google "Heat tolerant Cyms" to get some names and locations.??
For me I always figured there are a gazillion heat lovers so never ventured into the family.lol They are spectacular both in flower and plant form though gary

Purchased a cymbidium by an Apopka, FL grower at a big box store several years ago. It is doing great in Miami.