Most everyone knows that wood chip mulch is quite useful in landscaping. Not only can it be attractive, but by laying down a weed barrier first and putting the wood chips on top, it effectively keeps landscape areas free of weeds.
People who mulch with wood chips have primarily found it to be useful around bushes and shrubs, but until recently it has been deemed inappropriate for gardeners – at least until now!
But recent research has revealed that wood chip mulch made from living branches and twigs of less than 3” diameter may be the best soil builder there is! Called Ramial Chipped Wood (RCW), these wood chips build a stable humus into the soil (see point 7 below) like nothing else can.
I first learned about ramial wood chip mulch when one of the members in our garden club gave us a video slide presentation about it. He told us about the Back to Eden website that champions the cause, and shared his personal YouTube channel where he has posted numerous videos about his gardening experiences using Ramial Chipped Wood (RCW). After doing my own extensive research, I now believe it is the very best way to grow a garden!
Before I go further, let me make one thing clear. Bark chips, or wood chip mulch from larger branches may be well suited to perennials, but are not a good idea for the garden. They are very low in nitrogen and most other nutrients, and are not easily broken down by microbials in the soil, and are not converted to humus. DO NOT till them into your garden, as it can tie up the nitrogen for years, making that area of the garden unproductive.
1. It is usually free
2. It helps to neutralize soil pH
3. It almost eliminates weeding
4. It benefits the “good” organisms in the soil
5. It helps to reduce insect and disease problems
6. It adds valuable nutrients, reducing the need for fertilizer
7. It builds stable humus in the soil
8. More humus means better soil structure and softer ground
9. More humus means better aeration of the soil
10. Humus helps the soil to retain moisture
My friend who gave the presentation about RCW in our gardening club told me that tree trimming companies are more than happy to bring you all the ramial wood chip mulch you want. Most municipalities and utility companies just want to get rid of it, and will even deliver a truckload free of charge. Of course, $10 or so to the driver is always a friendly gesture.
My friend that introduced me to RCW gardens 1.5 acres, and has had many truckloads delivered to his garden, all for free! One day I heard a tree trimming company busy taking down a tree across the street from my house. I asked one of the men if I could get a load or two of their wood chips, and he was more than happy to oblige.
A few days later their truck showed up with my wood chips. The truck wasn't that big, and was able to maneuver down my winding driveway and dump the wood chip mulch by the gate to my back yard. Anyone who wants free wood chips can just look online or in the yellow pages for tree trimming companies in their area.
When nutrients are balanced out in the soil, soil pH tends to normalize between 6.5 to 7.0. This is one of the perks of using ramial wood chip mulch. It contains a balanced amount of most of the nutrients your garden needs. Just add ocean trace minerals, and you have a pretty complete package. Therefore, as the wood chips break down over time and feed the soil, the pH tends to normalize. (adjusting soil pH) If high pH was caused by salt from fertilizers, manures or irrigation water, then that salt needs to be remediated. I have found that about a quart per acre of MyCorrPlus works quite well for this.
When I visited my friend’s garden, I was quite impressed. I saw over an acre of raised garden beds growing a great variety of flowers and garden produce. What I didn't see was weeds. In my own garden, I have discovered that broad leaf plants just don’t have the strength to penetrate 4 inches of wood chip mulch.
Grasses can be stopped by cutting them short, then laying down a few layers of non-gloss wet newspaper, or cereal boxes, pizza boxes, or corrugated cardboard before adding the wood chips. Make sure newspapers or cardboard lie flat and overlap by 3 or 4 inches for best results. If a weed does appear, since the soil beneath the wood chips is moist and soft, it can be easily pulled.
When the soil is sick and out of nutritional balance, harmful nematodes, bacteria and grubs take over. Beneficial microorganisms thrive when soil nutrients are balanced, when there is good organic matter and humus that provides soil structure and airflow, and when there is adequate moisture. In this environment, the good microbials take over, displacing the bad. RCW helps with all these things.
Wood chip mulch is also provides a shield against UV rays which are deadly to microbes in the soil. In short, ramial wood chip mulch helps to establish and maintain a wonderful soil food web. (soil food web)
We have a cedar chest that discourages insects from entering. Did you know that cedar wood chips contain thujone that is harmful to the soil food web? Don’t use cedar wood chips for the garden. Pine wood chips don’t make the best mulch either. Most ramial wood chip mulch made from hardwoods make a wonderful food for soil microbes. Just keep the mulch moist, so that microbials can do their work.
Don’t worry if your ramial chipped wood grows Mushrooms. In fact, mushrooms and other fungi are what are needed to draw the nutrients from RCW and make them available to the soil. They are also quite accomplished at breaking down toxins and pollutants. Second, it is a popular myth that wood chips feed the microbes needed to grow shrubs, perennials and trees, but not for gardens. Why is it then that freshly cut forest lands make such good farm land?
In RCW plots you will find an abundance of the Mycelium fungi called white rot. This mushroom fungi is a wonderful thing for the garden, as outlined by Paul Starnets in his book “Mycelium Running”. As these fungus spread, they build rich topsoil, and a large community of beneficial organisms are attracted to take up residence, including fat, happy earthworms!
Insect and disease problems are caused by a sick, out of balance soil.
RCW helps to balance nutrients in the soil, bringing the leaf sap closer to an ideal pH of 6.4. All across the world those using RCW have observed a decrease or elimination of pests. A great companion to help RCW to balance nutrients in the soil is concentrated sea minerals. This not only provides potassium and magnesium, but it is fairly balanced, not too high in any one nutrient.
This balance of micronutrients makes it an excellent way to provide trace minerals that are missing in RCW. Numerous farmers and gardeners have personally told me that their insect problems disappeared when they started using sea minerals on their crops. Healthy plants with a leaf sap whose pH is around 6.4 just don’t seem to attract insects!
Ramial wood chip mulch contains a nice balance of N, P, K, and Ca. When I prepare to add a new area to my garden, I begin by doing a soil test (soil test page) so I can restore an initial balance of nutrients to the soil. But once my RCW starts to enrich the soil, it helps to keep the soil in balance and helps maintain long-term fertility.
Having said this, keep in mind that various crops utilize more of one nutrient than another. If a plant starts to scavenge nutrients from its bottom leaves to support fruiting and new growth, it is a sign that there is a shortage of a specific nutrient. A tissue test will reveal what is missing – more times than not the plant is missing potassium.
RCW contains cellulose, hemicellulose, lignin, many kinds of proteins, all the amino acids, nearly all the sugars and starches, and intermediate polysaccharides. It also contains countless enzyme systems and hormones, as well as polyphenols, essential oils, terpenes, tannins etc. that are associated to varying degrees with the nutrients necessary to generate and support life.
When you disk an inch of RCW into the top 2 inches of the soil, nitrogen will be tied up for a few months to break it down. If you don’t have much nitrogen in the soil, a product like blood meal (or even human urine) to meet this need for nitrogen. Disking the RCW into the surface of the soil speeds up the breakdown of nutrients. However, many growers prefer to use RCW as mulch. As a mulch, it can take 3 or 4 years to break down, but this method is preferred by some growers since it doesn't interfere with soil life.
By adding an inch of ramial chipped wood to the soil each fall, yields grow and grow, while other fertility measures become less and less necessary
The value of humus is common knowledge in the farming and gardening communities. It is the structure of the soil, making it possible for the soil to breathe, stay soft, and store moisture. What few people realize is that there are short-term humus and long-term humus. Short-term humus if formed from the breakdown of compost, green manures and animal manures. Within 1 to 3 years this humus is consumed by soil bacteria, so it must constantly be replaced. Excessive nitrogen applications cause bacteria to burn up this humus even more quickly.
On the other hand, there is a humus that is stable, (page 8) and can even last a thousand years under the right conditions. This humus is produced from the breakdown of hardwood branches and twigs of less than 3” in diameter. The lignins in these small branches and twigs are converted by mushrooms and other fungus into long-term humus, with the potential to give structure to the soil for many years to come.
One of the more serious weed problems faced by farmers is pigweed. These weeds thrive in compact, calcium deprived soil. Herbicides are becoming less and less effective. So what can work? How about building long-term humus and increasing calcium in the soil? Ramial chipped wood can help us to do both of these.
When soil becomes too compacted, the good aerobic bacteria that are supposed to live in the top 6 inches of topsoil can’t breathe, and the soil is taken over by harmful anaerobic bacteria. When this happens, disease and insect problems aren’t far behind. Humic acids contain proteins that glue particles of soil together, making soil more crumbly, and allowing air to permeate down into the soil, making mechanical aeration of the soil unnecessary.
When humic acid proteins glue soil particles together, it creates millions of tiny air spaces in the soil. These spaces not only help the soil to breathe, but give the soil a spongy feel. This spongy texture is able to hold a much higher percentage of water, so that when it rains, more soaks in, and less runs off.
Liquid humic acids are invaluable, and many farmers spray them on their land to help aerate and flocculate the soil. But if you use RCW, it won’t be too many years till your soil will be filled with humus and humic acids.
Even without the humus, a four inch application
of RCW helps to keep the soil moist. Wood chip
mulch acts like a sponge, yielding moisture to
the soil when needed, and storing moisture when
it isn't needed. Because the chips act so much
like a sponge, it is important to have moist
soil before laying down your RCW, or once they
are laid down you need a good hard rain or
watering to get enough water down to the soil to
moisten it. Once the soil is moist, mulches act
as a natural barrier to keep the wind and sun
from drying out the soil. This means that it
takes much less rain or watering to grow your
A note of caution. Shredded wood chip mulch that you buy at your lawn and garden center tend to create a matted clump that cause water to run off instead of penetrating to the ground.
Besides the 10 benefits listed above, RCW helps to protect plants from frost heaving, helps to control soil erosion, increases fertility 5 to 10 times quicker than manures, and transforms extra nitrogen into organic nitrogen and holds it in the top 6 inches of the soil, where it is available to plants instead of being leached out of the soil to ground water.
By helping with these 10 areas, ramial wood chip mulch truly is a problem solver for gardeners and farmers. If you like, you can continue to page 3, which tells how ramial chipped wood helps to create the perfect soil.
For years now I have given my lawn and garden a boost by applying liquid humic acid, mixed with ocean trace minerals. These humic acids jump start 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.