hello sir
In Bread sandwich method the top soil and sub soil are kept separated by inserting compost between the two layers of soil. Charcoal can also be inserted for better performance.
By feeding the micro (soil) organisms and maintaining soil moisture we can harvest maximum solar energy through photosynthesis.
The top soil is loose and contains more micro and macro organisms than the sub soil. The roots of plants, whether it is wheat or radish go up to a depth of more than 60 cm into the soil.
So it is important that the soil is healthy and the micro organisms live till a depth of about 60 centimetres. At the same time farmers must ensure that the top soil is not buried deep.
The top soil is removed and keep separate. IInd split the sub soil. In the third stage, add a thick layer of well digested compost over the split sub soil. Finally,replace the top soil over the compost.
This is called as soil sandwiching method.
Radish and greens can be sown on the edges.
Vegetables with wider canopy such as tomato, brinjal, lady’s finger and chilli have to be allowed wider spacing.