Sunday, March 17, 2013

Putting in the Garden

Turf in garden area 'weed whacked' to less than 1/2 inch tall.

As I mentioned a few posts back, I am putting in a new vegetable garden over an area that was previously 'lawn'.  I am using a technique described in Lee Reich's 'Weedless Gardening', where soil disturbance is minimized, by working from the top down.  This method uses a layer of grass smothering material to kill the existing vegetation and then a layer of soil or mulch on top of that layer to do the planting in.  By not turning over the soil, no new weed seeds are brought to the surface and the original soil structure is preserved.  (This method may not work so well on compacted soil or where there are some major soil chemistry problems.)

The first step in this process was to do a soil test to learn if there were any serious deficiencies or pH problems.  Turns out that the pH was good (6.9) and the nutrient levels were about right, save for a low phosphorous level.  Step two was to cut the existing vegetation down as low as possible.  I did this with the weed whacker.  Where there were vigorous clumps of grass I really scalped them down to the ground.

After flattening the cut vegetation, apply a fertilizer at a rate of 6 cups of a 5% nitrogen fertilizer for every 100 sq feet.  I had some Espoma Organic Lawn fertilizer with 17% Nitrogen (17-0-3), so doing the math, I only needed 2 cups of this per 100 sq. feet.  The soil test results indicated that I needed 1/4 phosphorous per 100 sq feet, so I was able to formulate that in with some triple phosphate that I had on hand.  Since over use of phosphorous in fertilizers is a major contributor to water pollution, having a soil test done and using only the required amount of phosphorous was the responsible way to go.

Now comes the new trick.  Rather than tilling the new garden, you just cover the garden space with cardboard or four layers of newspaper.  This will starve the existing vegetation of light and prevent germination of new weeds.  Since we had plenty of boxes and packing paper from our recent move, we were in great shape for this.  I chose to use paper to cover over the areas that would be the new planting beds, and cardboard for the paths since it would take longer to break down.

Cardboard was laid out for the paths.  Landscape staples held it in place.
My new Weed Wrench was handy for holding down the stack of packing paper.

After getting the paper and cardboard down on the ground with the help of some landscape staples, the paper was wetted to get it to conform to the ground.  The beds were covered with a layer of soil, and the paths were covered with a couple of inches of mulch.  This installation would have been easier on a calm day, however it was kind of blustery the day I was working.  The stables really came in handy to hold things down until I could lay down the initial layers of soil.

The planting beds in this garden are 3 feet wide and 12 feet long.  The width was chosen so the entire row could be easily accessed from the path.  By not stepping on the planting beds soil compaction is minimized and good soil structure is preserved (and no digging!).

I had 3 yards of screened top soil/leaf compost blend delivered...
and carted it down to the garden to build up the planting beds.

Now I just needed to make a 'few' trips to move the soil onto the new beds.  It would have been much easier if I could have had the soil delivered closer to the new garden, but alas that did not work out.  So about 16 trips with the wheelbarrow later, I brought down enough soil to cover the beds 3-4 inches deep.

In addition to the vegetable beds I am also preparing perimeter beds where I will put in some pollinator friendly natives.  These include Aquilegia canadensis, Asclepias tuberosa, Monarda fistulosa and Rudbeckia hirta and R. triloba.  These plants are also listed as deer resistant.  As such they are serving as part of my multi-layer deer defense scheme.  In addition to these deer resistant plants, I will plant some of the annual False Pennyroyal, Hedeoma pulegioides.  This is not listed as a deer deterrent, but it packs a pretty sharp minty odor when touched.  I'll watch to see how the deer treat this plant.

Again, I used paper under the perimeter beds, so that root penetration will be easier.

You may have noticed the double set of fence posts.  The outer set are from an electric fence that the previous owners had used for some sort of corral.  The inner set will be for a plastic mesh netting fence that will be partially buried.  That should keep out the rabbits and ground hogs.  The double fence method is supposed to deter the deer because they are not able to judge the width of the double fence and will be uncertain about making a safe landing on the other side.  I'm not planning on turning on the juice to the electric fence unless I have to.

The main beds and paths are all done.
Just need to prep the back edge for planting the Pennyroyal.

The final step was to cover the cardboard paths with a layer of mulch.  We had this on hand from some trees that we had taken down last fall.  The mulch will hold down the cardboard and suppress weed growth from both above and below.

It's really strange to be working in the garden in early March.  Back in Boston I wouldn't come out to the garden until late April.  I wanted to get an early start putting this garden in so that the layers of paper had a chance to suppress the old vegetation and then begin breaking down to let the roots of the new plants through.  Once the fencing goes up in a couple of weeks I will do an update.