Sunday 26th January 2014 - Terracotta Pot Candle Heater

Too wet to do anything down the allotment today - So I went to B&Q to pick up 8 2.4m lengths of treated timer to make up some more pop bottle frames and I'm kinda getting overrun with them down there and want to make up pop bottle fox proof cloches ready for warming the beds in late Feb / March

Also picked up a pH & Soil moisture tester reduced to £3 so that I can check the pH of the beds and perhaps water as required in the new greenhouse rather that have it too wet in there, and a couple of terracotta pots for the candle heaters I intend to try in the greenhouse and the cold frame. I intend to do some trial runs and monitor the inside and outside temperature to see if these candle powered terracotta heaters really work. 

I think their diagram is wrong in that as heat rises the hot air would escape from the top and draw air from the bottom of the pot to be heated on the way i.e. a vented chimney with their diagram where does the replacement air come from if its all flowing out? - basic physics really - God I'm turning into the gardening equivalent of Sheldon from the Big Bang Theory