nutrient dense grass

Vegetable Garden Mulch
That Builds the Soil

Although I have used numerous types of mulches, my favorite vegetable garden mulch for most applications is ramial chipped wood (RCW), made from small, freshly cut hardwood branches run through a wood chipper.  Utility tree trimmers are usually happy to give these wood chips away for free.

Four inches of RCW mulch not only helps to choke out weeds, help to hold moisture, and shade the ground from deadly ultraviolet waves, but as the soil breaks it down it can transform even the poorest of soil into soil that would be the pride of any gardener.

I have written some web pages to share why Ramial Chipped Wood can literally be a gardener’s dream come true. In the right margin you will see a description of each of my RCW pages. Which of these topics might be helpful to you?

What RCW is 

Ramial Chipped Wood is produced by running live twigs and small branches no larger than 3 inches in diameter through a chipper.  These smaller branches and twigs are the richest part of the tree, containing 75% of the minerals, sugar, protein, cellulose and easily digested lignin, and a favorable carbon to nitrogen ratio of 30/1 for smaller branches and twigs up to 170/1 for branches 3” in diameter. They make a beautiful vegetable garden mulch.

The carbon/nitrogen ratio of larger branches goes from 400/1 to 170/1. Ideally, RCW should be chipped to a length of 3/4 inches to 1 1/2 inches.  Shorter than 3/4 inches will hinder air flow down to the soil, and longer than 1 1/2 inches means that the fungus utilized to break it down will be hindered by the bark from getting to the wood, making decomposition a slower process.

What RCW is Not

Ramial Chipped Wood is NOT dead wood that has been chipped.  The beneficial properties come from freshly cut branches.  It is not wood chips from branches over 3” in diameter. Such wood is very low in nutrients, and the soil finds it very difficult to break down the lignins and integrate this wood into the soil.  Therefore, chips from larger branches have very little value to the soil. (On a side note, this helps to explain why tree bark, wood shavings and sawdust make such poor soil amendments)

RCW: greatly undervalued 

For many years these smaller tree branches have posed a great burden on city utility crews and crews that clean up downed trees, who end up paying to dump them in city landfills.  RCW is considered as trash to the timber industry. Worldwide, billions of tons of these small branches are being quite literally thrown away.  What a shame.  RCW can be turned into vegetable garden mulch, a mulch that has such great capacity to transform poor soil into rich soil, both by feeding soil microfauna and microflora, and by creating long-lasting humus (pg. 11) in the soil.

Nutritional benefits of RCW

Branches under 3” in diameter have considerably more nitrogen, phosphorus, potassium, calcium and magnesium than larger branches. Branches without leaves (as is found in the winter or early spring) and branches with dead leaves (as found in the fall) are primarily broken down by fungi, and work to build rich humus rich soil.  

For the initial application of RCW, it is best to avoid branches with green leaves, since the bacteria needed to break down green leaves can take over and displace the desired “white rot” fungi, or basidiomycetes.  Fortunately, the breakdown of brown leaves works in harmony with white rot. This is just another reason why it is best to make your initial application of Ramial Chipped Wood vegetable garden mulch in the fall, winter or early spring.

Nature relies heavily on trees for soil building. For the gardener, taking advantage of free wood mulch from local tree trimming companies is almost a no-brainer.  More organic matter means more fungi. These fungi will help to mop up excess nitrogen in the soil and store it for later.  As the fungi die, their bodies then become food for various bacteria, further growing and diversifying microbials in the soil.

Since RCW is made from smaller, newer growth, it contains a higher amount of living tissue, which in turn contains more nitrogen rich proteins. This extra nitrogen gives fungi some of the fuel they need to do their work. If any is left over, the fungi immobilize it in the soil.

When an inch or less of RCW is integrated into the soil, (page 5) it will be broken down faster, and fungi will tie up whatever nitrogen there is in the soil to do their work.  Important: When RCW is used on top of the soil as a mulch, it is broken down slower, and doesn't tie up any nitrogen from the soil.  This makes it possible to apply RCW as a vegetable garden mulch any time of year.

It is also important to note that neither RCW nor other mulches contain the full spectrum of needed trace minerals that have been leached out of our soils down to the ocean.  I personally use trace minerals from the ocean to recycle these trace minerals back into my garden.  Other than trace minerals, Ramial Chipped Wood offers a fairly complete array of nutrients.

Application of RCW

For our purposes, RCW mulch is built up to around 4 inches deep. This is deep enough to choke out most weeds, but still allow airflow down to the soil.  When applied in the fall, some of the nutrients in chipped wood may already be available to the soil by spring planting time, especially if a special mixture of humic acids and other nutrients are applied over the wood chips. As I mentioned above, when applied in the fall, an inch of RCW may be tilled into the top 2 inches of the soil.

For years now I have given my lawn and garden a boost by applying MyCorrPlus, which contains ocean trace minerals. This soil conditioner jump starts the soil building process by gluing together fine soil particles, building a crumbly friable soil structure, while the ocean trace minerals supply an incredible buffet of micronutrients which have long since leached out of our soils.

History of Ramial Chipped Wood

In the 1970’s, gardeners in Quebec, Canada began experimenting with Ramial Chipped Wood as a vegetable garden mulch.  It is now gaining some popularity in Europe, and especially in France.

And why not?  When hardwood forests covered the earth, soils were rich with humus, full of life, and very fertile.  It is so totally easy to restore this richness and life to our soils, just by applying RCW as a vegetable garden mulch.  

Next page - How RCW solves gardening problems

(Return from Vegetable Garden Mulch to Fertility Soil)