Got Dirt!

Last week I added two new 4’-0” by 4’-0” raised beds to my garden.  The beds were made out of some 2×12’s I was able to salvage prior to  them hitting a dumpster.  Last weekend I built the frames, added some hardware cloth to the bottom of the beds and dug them into the ground so they were level.

I collected most of the dirt making supplies last week.  I follow the basic recipe Mel Bartholomew writes about in his book “All New Square Foot Gardening”.  The mixture is essentially 1/3 compost, 1/3 peat moss, and 1/3 vermiculite.

I have made the same mixture basically for the last three years for my raised beds.  Making dirt takes time and money, so I basically make enough dirt for two 4×4 beds per year.  This year I spent a little more time trying to locate an economical source for the vermiculite.  Lowes and my local garden center had 2 cubic foot bags as the largest size they carried and these bags were $25+ dollars per bag.  After a little research I found a local Agway that had vermiculite for around $25 for a 4 cubic foot bag, so I bought 2 bags.

In addition to the vermiculite, I picked up a couple blocks of peat moss.  The 3 cubic foot variety at Lowes was around $9 per block.

Finally, I purchased bags of compost ranging from bags of composted cow manure, mushroom compost, and lobster compost prices went from $2 – $6 per bag.  I am currently working on my own compost this year to hopefully offset some of this cost next year.

With all of the materials on hand, I laid out a tarp on the driveway, got the boys together with the appropriate yard implements and boots and started making dirt utilizing the following process.

Step 1 – Shake out a block of peat (3 cu. ft.) on the tarp, loosen with a rake and soak with water.  You will need to move the peat around to get it well saturated with water.

Step 2 –  Shake out a bag of vermiculite (4 cu. ft.) on the saturated peat moss.  Soak with water and then rake into the peat.  I also lift the corners of the tarp to help mix the materials back to the center of the tarp and then rake the material out again.  When the the mixture is well distributed its time for compost.

Step 3 – Add your compost!  I used 8 bags of various compost (6 cu. ft.) dumped onto pile, and mixed thoroughly with a rake so that all the materials were evenly distributed.  If you have been keeping track at home my ratios of peat/compost/vermiculite are a little off of the thirds I mentioned above but I was working with the bags I had and felt going heavy on the compost would be a good thing.

Step 4 – Time to load the dirt up and add it to the raised bed on top of some hardware cloth and some landscaping fabric.  If you want less work mix your dirt near the bed you are filling.  I have all this free child labor that loves moving dirt plus I find it easier mixing the dirt on the flat driveway so I made my dirt off to the side on my driveway.

Step 5 – A quick re-cap.  My beds are 4’ square by approximately 1’ deep.  Basic math gives us the volume of the bed at 16 cubic feet (4 x 4 x 1 = 16).  My dirt materials were 3 cu. ft. of peat, 4 cu. ft. of vermiculite, and 6 cu. ft. of compost for a total of 13 cu. ft. of dirt.  Now everything is loosely mixed and in reality fills one bed to the top of the bed.  The dirt will settle over time as you water and work the bed.

Onto the second bed!