Greenhouse seems to be going well. Tomatoes, melons, aubergines, and stawberries all thriving. There is no space heating in the greenhouse, only a 120 W ground heat cable in the bed (tomatoes and melons) and a 60 W cable in the bench sand tray (aubergines and chillis). Heating is controlled by a small computer. Although thermostats are cheap enough singly, the cost mounts if you want more than one, and I had a computer spare. Also I may add automatic watering and humiditiy control later.