How well will a Dutch bucket system work for tomatoes in the winter? What I am thinking is placing a rocket stove in the center of the green house with a 30 foot pipe run through the greenhouse and back covered in sand and sealed with a dirt and straw mix. Set rocks on top of that to make a bench for the buckets to set on. I have read of theses heating systems putting off as much as 100 deg for several hours so I may need to insulate it slightly under the buckets to keep the tomatoes from getting too warm. My main question is how will the tomatoes do with wide temp swings in a winter greenhouse?