Hi Ron and Ton,
My conditions are not very seasonal, since I am right on the equator in central Ecuador. I am an ecologist working the evolution and conservation of endemic tropical plants, mainly orchids (since half the local endemics in my area are orchids). But bulbs (particularly amaryllids) also show a lot of endemism here, hence my interest. My interest in Tigridia has no scientific component whatsoever, they are just plain beautful, period.
My climate is far more equitable than yours. Lows are around 14-17, highs are 20-23, with the lower temperatures occuring at the height of the rainy season (which is right now). Humidity is almost never below 50% and mostly above 70%; most nights have 95%+ humidity.
Nevertheless there are some native amaryllids here. One of our endemics is Phaedranassa tungurahuae, which grows wild in my yard. Just a few kilometers away the weather changes due to a rain shadow effect, and there we have several more Phaedranassa species: P schizantha (two "subspecies" which may be distinct species) and a yellow taxon I found, which may or may not be a known species. I also found an unknown population of Pyrolirion in the same area. We have the irid Ennealophus foliosus spruceanus too.
In lower, wetter, hotter areas we have Eucharis formosa. Farther south, I recently discovered a new species of Eucharis which will be described by Alan Meerow, Nora Oleas, and myself when we find the time to do it...also a new Stenomesson on cliffs in an otherwise very wet area. I believe there are still more species to discover, especially in local isolated rain shadows and in isolated rock formations surrounded by inhospitable (for bulbs) wet forest.
I grow most of these plus a few other native Eucrosia, Phaedranassa, and others.
Anybody have experience with Tigridia augusta?
Best, Lou