Since I grow many seedlings, I can tell you that I have some disappear every year. One of my favorite seedlings from last year has completely disappeared over our mild Winter. I fear it is a goner. It has dormant genetics in it's pedigree. It's siblings have not totally disappeared and are sending up new foliage. (I know each seedling is unique.) If they are heat sensitive, why don't they die or drop their foliage in the Summer/Fall? Why do they typically disappear during the Winter months? I had a very mild Winter this year. It never got into freezing temps. Any cold temps were only overnight or early morning and then the temps warmed up once the sun started shining. Very brief temps in the high 30's for only a few days this Winter.
If a daylily plant is deciduous, when would one expect them to send up new growth? Early Spring, late Spring, Summer? Or as I fear .... never. They may have died.
