Soil: If You Build It, You Can Grow and The Solution to the Mystery of What's Buried in my Plot

Soil.  It is the most important thing in growing a productive garden whether you are growing ornamentals or edibles.  Gardeners everywhere talk about it.  Businesses are built around it.  Entire books are dedicated to it.  But, how do you get it?

As with all things, ask 20 gardeners this question and you will get 20 different answers.  In my opinion, the truth is that there are many roads that you can take to lead you to the same destination.  But, the one thing these many roads have in common is good compost.  You have to keep enriching your soil with good quality organic material that will feed your dirt and the life within it.  John Jeavons, the master of biointensive planting, who has been teaching people how to make any land productive since 1972 and whose methodologies have been implemented in 141 countries to grow food for the hungry, says, "Develop soil structure so the plants will have a 'living sponge cake' in which to thrive."

Okay.  Got it.  Sponge cake.  And, then I got to asking myself how I could make my own sponge cake large enough to fill an empty raised bed which will require roughly 27 cubic feet or 1 cubic yard without compost and without spending a fortune?  And, have it be productive in the short term future?  The research began and The Lab, my plot at the Dunwoody Community Garden, was born.  I went to the bank and withdrew $130 of my fun  money that I earn from doing market research surveys or save from birthdays to accomplish this with.  Cash in hand, I was off looking for the road to soil traveled by those on a shoestring budget! 

In my research, I did not find one single recipe that I could use to make my own living sponge cake that would fill an empty raised bed.  There are many.  But, I did read about many methodologies used all over the world and many of them relied heavily on one very inexpensive ingredient - bales of straw.  At $4.50 a bale and with only three required, it's easy to see why this quickly became my plan.  But, I wanted this to be productive quickly and so I decided to follow the very basic and easy lasagna gardening method.  The idea behind lasagna gardening is that it is a no-dig, no-till, compost-in-place method where everything breaks down together over time and creates a very rich soil that will help your plants thrive.  The solution to my lack of compost that sounds a lot like a living sponge cake to me!  (You can read about it here and here and here.)  In short, it is the following:

• brown material
• fertilizer - equal parts bone meal and blood meal
• green material
• fertilizer - equal parts bone meal and blood meal
• brown material
• fertilizer - equal parts bone meal and blood meal
• compost or soil dug in to the middle
• plant

In my case, I chose to use the following because the materials where relatively inexpensive and available and because this was a combination I had read about that seemed to work.  To give you an idea, all of these materials together cost me about $100.

• 4" shredded newspaper, no glossy paper
• 4" alfalfa hay which equates to 2 bales purchased from my local, livestock feed store
• 3 wheat straw bales broken up and spread across the bed
• 2 bricks of coir which is not in the actual recipe but I decided to add it to help the bed retain moisture in the unbelievable southern summer heat.
• 6 bags of pre-made soil spread across the top to actually grow in in lieu of compost because I didn't have any
• 1 bag of bone meal
• 1 bag of blood meal

So, I layered all of this in my bed and the truth is that it was waaaaay too much for that 10" high raised bed.  But, I knew it would break down and settle over time, so I stuck with it. At the time though, I had this large mound held together with burlap and twist ties.  I watered it well, tossed in some buckwheat cover crop seeds and the fun officially began! 

A photo of the bed upon completion, 6/15/2011

And, it has been fun.  All sorts of people have asked me what I've got going on in there, my overflowing, hugely mounded, raised bed.  One friend and fellow gardener, Farmer Bob, went so far as to ask me if I had my husband buried in there because he hadn't seen him in a while.  Rest assured, he's alive and well.

The buckwheat cover crop grew well and then I tossed in some cowpeas with the idea being that I could harvest them when they are ready and they will fix nitrogen in the soil for the next crop.  Here's a recent photo of how things are progressing:

No loss of productive time even though the soil is in progress.
Photo taken 8/252011

It's a little hard to tell, but you can see the outline of the big mound of soil ingredients in there.  I have not added anything else except water to this bed since I built it.  I pull back a corner every once in a while to see how things are looking.  So far, I have learned quite a bit by trying this method.

1. There is an even thriftier way to do this.  Skip the alfalfa hay.  I am not convinced you need it and it was the most expensive ingredient of the bunch.  
2. I still think you need newspaper if you plan to grow on top of anything that is already growing.  In my case, my plot had grass growing.  The newspaper is sufficient to suppress its growth so it doesn't come through.  
3. I am not sure that you need the pre-made soil.  If you don't have compost, skip the soil and stick with the coir.  The coir is a perfectly suitable growing medium with the added benefit of retaining moisture.  The straw drains freely, so the coir helps balance that.  Or, if you have homemade compost available, by all means use that.

And, the experiment continues...