Dig!

We have very rocky, poor soil on our hilltop. I use raised beds for my vegetable gardens. I have used Mel Bartholomew's Square Foot Gardening mix of peat moss, vermiculite, and compost for a few years. It has lots of advantages, the greatest of which is the lack of weeds (I pulled 3 weeds from a bed one season). However, since it consists of most or all purchased materials, this method is not economically feasible on any scale.
I have read of the wonders of double dug beds, but assumed they were too labor intensive for this busy stay-at-home mom. Double dug beds, in a nutshell, involve digging two shovel depths into the ground.

I thought I'd try a combination of the two ideas. So I dug one shovel depth down and worked in some purchased organic soil. The overall depth of loosened soil was almost equivalent to a double dug bed. Here is the sorghum growing in this space.

Not 50' away, planted on the same day, receiving the same light, is the other sorghum. I dug about a half shovel depth and worked in the same purchased soil. 

I am completely sold on my hybrid method. Obviously the digging depth has an enormous effect on the plants. I plan to garden in well-dug fluffy soil from here on.