cybersix said:So, deadheading is still good?
That depends on the time at which the flower is deadheaded.
cybersix said:is it the same for the spent flower?
It is the same for the spent flower. Material that can be reused is exported from the dying flower to other parts of the daylily plant.
Bieleski studied the movement of resources from the flower to other parts of the plant. He considered time zero to be midnight during the night before the flower opened and examined the flower up to 34 hours later. Resources were moved from the flower as it aged and died and transported to other parts of the plant during that time.
I seldom deadhead the flowers but when I do then it is only after they have developed their special layer that allows the drying flower to be easily removed from the scape at the special joint between the flower stem (pedicel) and the scape. The export of resources from the dying/drying flower should have more or less ended by then.