Is there a time of year that is less extreme? If sunrise/sundown doesn't work during that period, grow autoflowers.
if you find a pheno that is more robust than others, start using clones.. make a mother-plant out of it.
An enclosure of some type with vapor barrier and a humidifier might be needed. Humidifiers are cheap and once plants are grown out, they might maintain a proper humidity on their own.
Build a greenhouse... find robust phenos.