In reading the book or watching the movie “Holes” you develop a good sense of how difficult it is to dig out dirt in a hot arid environment. Admittedly it was difficult for me but it could have been much worse. In many locations around Tucson people commonly complain of hard packed dirt and of caliche - a hard collection of minerals (primarily calcium carbonate). I would not be surprised if caliche was the main ingredient in concrete. Often trees and other deep-rooted plants will perform poorly if the gardener does not break a hole through a sub-surface layer of caliche to allow for water drainage. I borrowed a neighbor’s caliche bar – a metal rod with a spike on one side and a wedge on the other – and used it along with my shovel in digging my winter garden bed. While digging I encountered quite a few small ½ inch to 1 inch chunks of the caliche but found the process to be otherwise uneventful. Soaking the area with water the night before digging always helps.
Before I began digging I laid down my blocks to the perimeter desired. I removed soil down to the 2 foot mark, leaving enough dirt on the inside of the garden bed to be a good foundation for my underground weed block. To create my weed block I “planted” blocks vertically in the ground on the inside of the garden perimeter and cut a metallic insulation material to fit snug against the outside of the planted (vertical) blocks. Thus the Bermuda grass would be blocked from getting its tendrils into the garden by the metallic insulation and by the vertically planted blocks on the bottom and by the horizontal block perimeter on the top. I cannot stress enough the long-term benefit of keeping out weeds from the beginning. It is wonderful.
To go with picture: Digging is good work for the young and healthy.