Can anyone recommend an inexpensive automatic greenhouse watering system? I have a 6' x 8' greenhouse at the moment, although may buy a slightly bigger one later, and am often away from home for a few days at a time - apart from my two weeks annual holiday. I can have 4 grow bags, a few seed trays and one or two plants in the greenhouse at varying times - sometimes all at the one time. I have an outside water tap but the greenhouse is at the opposite end of the garden from this at the moment. Any suggestions would be appreciated.