Two very special types of roses bloom in Underlight, in mythology (and probably in reality) created by the two gods, one for each. The respective roses are held in high esteem and religious significance by the two followings. They also have some minor and major powers; they make excellent boons. As much as I would rather not use the 'reward at the end method', their reputation as religious items makes it unlikely that they will be given away to strangers until some service has been performed.
The times that the buds will open are of course affected by the Spell of Reversal - the day/night periods given here are the times they will be active in the absense of such drastic magical effects,
Sun roses have golden blossoms which only bloom during the day. When open they give off a faint golden light, in a darkened room this provides just enough light to not run into anything. When a bud is cut off from a bush, it will eventually become somewhat dry and appear dead, but holding one in one's cupped hands and blowing gently across it ('breathing the life into it') causes it open up and emit light once more, but it still only opens during the day and this will have no effect at night. It closes at sunset. A much more potent effect can be achieved by burning such a bud, if this is done at night, the night will turn to day for a brief period ('Lighting the moon on fire.') (this lasts perhaps an hour at most.)
Though considered holy, most family or other groups whom worship Shine maintains their own planting of sun roses; however the first seeds that family/group receives should be from a priest/priestess.
The counterparts to the Sun Roses, the Moon Roses have silvery blossoms which only bloom during the night, also giving off just enough light to see by. 'Breathing the life into' detached buds at night will also open them up to provide silvery light until sunrise. Crushing a bud during the day will cause it to become night for a short period ('Crushing out the sunlight.')
Moon roses are considered too holy for the masses, only priests/priestess of Shimmer may tend them, and it is near blasphemous for someone else to touch them unless they are given by a member of the clergy.