YOu don't necessarily have to double dig each year. IN the book "How to Grow More Vegetables" Jeavons says once the soil is in good condition you would only double dig it if it became compacted and even then you could use a broadfork (what he calls a U-bar) to aerate it.
So no, you don't have to double dig every year to practice Biointensive.
Let's get him boys! We'll make him read this tiny ad!
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