Viridescence: Emerging with white or yellow leaf color that ultimately
become increasingly green with the season.
Lutescence: Emerging green or chartreuse and turn to yellow or whitish
yellow. This process is usually more subltle and often less discernable than
viridescence as frequently it involves only a very slight change from a greenish
cast to a yellowish hue.
Albescence: Albescent taxa have yellow, yellowish green, or green areas
that turn to near white, as in H.'Janet'. Frequently, yellow-margined taxa turn
into white-margined ones, for example, H.ventricosa 'Aureomarginata'. Whitening
due to bleaching by overexposure to strong sunlight destroys color-forming
plastids, so is not true albescence.
All of the above from The Genus Hosta, George Schmid