Still in the nursery pot?? After several YEARS?!!! You brute!
Seriously, put 'em in the ground--6 hours of sun or more--great drainage--afternoon shade if you think too hot--good acidic soil w. lots of organics--fertilize--- lots of mulch to cool the roots---give them a chance! They grow and bloom ok here in New Orleans, zone 8B /9.
Or you could just smell all those plumerias!

The rose garden in Kapiolani Park (Honolulu), if it is still there, requires coddling to keep it going. And it's all/mostly hybrid teas. A hybrid Rugosa like 'Hansa' seems most unlikely to succeed, except, perhaps, at a high altitude.

My recently departed grandmother, who lived in Hawaii more than 98 years, used to remark on how lousy roses were there, relative to here on the mainland. Her handful of hybrid teas sure didn't seem to have the horsepower of those here. Likewise for those in the Park.

Thanks for the responses. I have just seen the first new foliage coming on since I put them in the ground 5 (?) months ago, so hopefully they will take off and do well. They are definitely getting enough sun, in fact they might end up with too much by the time summer is in full swing. Maybe I can plant something taller next to them to shade them in the afternoons. I will let you know if I ever get a flower!