Succulents
Succulent is a term for a wide group of plants that have fleshy thick leaves that store water.
With succulents you can have the best of both worlds. A house plant that can be grown outside through the warmer summer months and then brought back inside for the winter, placed onto a window sill in the house or conservatory or if you wish you can keep them in a greenhouse.
Good drainage is the key factor when growing these type of plants.