I would say room temp is fine. Are you doing them in your GH or in the house? I don't have a GH, so mine are all sown in the house, so whatever temp my house is, around 70, is what mine sprout at. There have only been one or two crosses that didn't sprout well for me. Also, I have not had an arborea seed sprout yet.
Shawn

Thanks Shawn I am still trying to fugure this gh out...I will kick als tomatoes out of the kitchen and put in the gh and set up shop on the dining room table...I think it is too hot in the gh and maybe I am frying them...Good luck with the arborea :)

I agree with Shawn, about room temp but I'm surprised they aren't sprouting in your GH, even with the temps being a bit higher. Maybe the soil is too wet? How long ago did you sow them? Shawn I had very low germination with arborea seeds, maybe 1 out of 10 sprouted.