The Greenhouse is now fixed. See this thread for details: Stone’s Throw Greenhouse Season’s Update! *12/13*
The new store venue Greenhouse has an issue where Winter will not stay out and make your plants go dormant.
The Glass roof sculptures are not actual roofs, making the game think there’s no roof on the green house
SimGuruCopeland has posted a solution on how to winterize your greenhouse and what to take into consideration if you build your own.
See here for the details: Winterizing the Stones Throw Greenhouse.
The Store Team is working on a more permanent solution.