I have selected 3 different potatoes, Pentland Javelin (first early), Maris Peer (second early) and Kerrs Pink (main crop) for the trial.
The first thing I have had to do is build simple wooden frames to support the bags. These were built from 50x50 uprights, 50x25 horizontal rails. The assembly was done with 65mm decking screws. I cut all the wood from offcuts of pressure treated 150x50 I had left over from building a pergola last year:
I then placed the bag inside and stapled it to the top of the frame:
This was repeated for 3 other bags:
Now we come to the alchemy! Each bag was loaded with approximately 150mm of well rotted farmyard manure:
This was topped off with 100mm of general purpose compost that was levelled off and tamped down:
The compost was well watered and the chitted potatoes were pushed into the compost, 9 to a bag:
The potatoes were then covered with 200mm of straw:
And that is it so far. The theory is that the shoots are allowed to appear around 150mm above the straw and then 50mm more straw is added. this process is repeated until the overall height of the straw/compost/manure is 750mm.
I will update this post on a regular basis as things progress.
As a comparison I am planting some of the same seed potatoes in the "conventional" manner in my vegetable beds I so will see how the two methods compare.
Thanks at this stage are due to my very good neighbour, Jim Coleman, for the donation of the manure and the straw!