Dig, Baby, Dig!

Now that I have begun to work in my newest garden beds, I’ve come to appreciate some of the pros and cons of different soil preparation schools of thought.

Knowing that too much information would surely overwhelm me, I stuck with one source of gardening knowledge, my Sunset publication of “Edible Gardening”.

I read its treatise on the merits of double digging versus the time-honored tradition of rototilling.  Even though I was relieved to read that, in general, rototilling was frowned upon by Sunset, my back wasn’t looking forward to all that double digging.

Double digging is a bed preparation method that aerates the soil, improves drainage, and creates an optimum environment for strong root growth.  It is also labor intensive and rigorous.  However, I must admit, by the time I reached the end of my gardens, I began to appreciate double digging as a form of exercise that melted off the extra pounds of winter.  To learn more about double digging, read this quick set of instructions at http://www.wikihow.com/Double-Dig-a-Garden and watch this short video at http://www.youtube.com/watch?v=W85QmZgDxFk for a good demonstration.

Then last summer, I went to a class about gardening and learned about no till gardening.  The premise behind no till gardening is this: rototilling a garden leads to compacted soil and soil erosion while it disturbs beneficial soil structures.  See http://desertification.wordpress.com/2008/02/26/no-till-gardening-sustainable-alternative-to-the-rototiller-daves-garden/ for more information.

Because I was preparing new beds in an area formerly inhabited by aging trees and shrubs, I figured that the soil would be full of roots that would make double digging very difficult.  The no till option appealed to me because I wasn’t relishing the idea of double digging through all those roots to loosen the soil for beds.  Instead, my plan was to clear away all the vegetation, cut trees and shrubs own to the soil level, and build the gardens up from there.

I cleared away all the shade plants, weeds, and branches and raked the area level.  I marked walking paths and beds.  I put down a weed barrier on the paths and heavy piles of paper on the beds.

Then I piled on lots of organic material: grass clippings, compost, shredded leaves, manure, more compost, and I topped the beds with a thick layer of oat straw.

I piled the paths thick with wood chips from the dump and the whole garden looked so beautiful.

This spring, I pulled back the straw and planted my seeds: lettuce, peas, and chard.  The soil was rich and loose and full of happy worms.  All looked like paradise in my no till garden.  Then the hardy weeds can back.

I was happy to transplant the errant ferns into another garden.  But I could not tolerate the lily of the valley coming up in my lettuce patch.  As I’ve said before, it is very poisonous.

The moral of this long narrative is this:  I believe that I could have eliminated 99% of the weeds if I had double dug the bed first.  I could have sifted out all the plant parts I had missed when I initially cleared the bed in the double digging.  My gardens that are most successful (weed free and growing good food) are a combination of double digging and no till.  I like the idea of loosening up a good two feet of soil depth before establishing a bed, especially if I am planting root crops.  Once this is accomplished, I pile on the organic material to feed the soil from the top down.  I achieve both goals this way and create soil with enough loft to grow long carrots while disturbing very little of the soil’s natural integrity.