Heat and humidity does not seem to bother most varieties and the T. formosana types seem to thrive on it. Fertilization is best achieved by a balanced slow release fertilizer like an Osmocote 8-9 month product. Some varieties are heavy feeders and you can tell by the appearance of anemic leaves that food is needed. They appreciate organic foods like fish emulsion at half strength. My experience with high strength soluble fertilizers is that the leaf-tips will burn on these plants.
Pests can include root or vine weevils, slugs and snails, and aphids to a lesser degree.
In the garden, tricyrtis are a joy, as long as they don't dry out. Their leaves are elegant and substantial and the waxy, exotic flowers are a treat worth waiting for. Carex varieties can form a nice grassy counterpoint to them. They are quite at home with Hosta, but one should avoid the larger thugs that can smother the poor dears. Groundcovers like Maianthemum, Viola, and Asperula support the plant visually.