As any gardener or farmer knows, the success or failure, work load, and attention necessary of growing things is all in the soil – it’s fertility, texture, depth, ability to hold moisture and general health. One of the Permaculture Design tenants is that you never leave soil open or uncovered. Many farmers do anyway, just putting plants in a row, with open soil all around the plant. Some plants will do alright but what happens is the soil on top dries out, gets blown around or rained on and soil is lost in both cases. We are loosing farm soil at an alarming rate. The USDA tells farmers if they only loose one to one and a half inches of soil a year, it’s good soil management.
It takes nature a hundred years to create one inch of top soil. So, basically when this attitude is taken, using heavy farm equipment and industrial style farming, we aren’t growing or husbanding the soil, we are mining it. When we run out of ‘friable’ (crumbly fertile soil suitable for growing crops), we can’t provide food for people and we will all starve. We worry about peak oil. Peak farm soil and farm land is much more at hand and dangerous.
Without food civilizations crumble because, simply, people need to eat. When they start to experience famine they tend to destroy any civilization around them in their mad rush to eat and feed their families. We take food for granted. Food crisis is already here, and without wise and speedy restoration of our food system, famine is coming sooner than we think. A lot sooner. I’m not a doom and gloom person. I just make my living knowing trends in agriculture being a consultant. And I know our food system is already in danger. Food prices alone have gone up more than 75% in the last 4 years. Have you noticed box contents are smaller for the same price, meat is sky high, everything is more costly.
But study after study by the UN and other international organizations have found that instead of the big industrial sized millions of acres style of food growing using ‘mono-cropping’ (one crop grown by the thousand acres like corn, soy, canola – rape seed, etc.), what provides more food in a more sustainable way and in actual fact CAN feed the world is the small family farm using sustainable practices. The number of small family farms is again increasing as more people are seeing the wisdom of this and wish for that lifestyle.
So, back to the subject of the soil, this idea of never leaving soil uncovered or unplanted begs the question, what does that mean?
In a small backyard garden or small farm, when one crop is done being harvested, the space it took up must be prepared for the next crop quickly and planted. In a backyard garden when a few carrots are pulled, the wise gardener immediately has some other succession crop like beets or lettuce which takes up about the same amount of space ready to put in, either by seed or transplanting seedlings already prepared.
Or a cover crop is planted such as clover, rye grass or other ‘green manure’ plant which when turned back into the soil adds to its fertility.
In a careful garden, where soil is constantly in need of fertilization due to intensive planting, it means that not only is the next crop put in or a little space replanted, but it also means each time digging in a little something to add fertility like some garden waste or a handful of compost or coffee grounds. And until the lettuce gets big enough to shade the surrounding soil which is now open and uncovered, it should be mulched.
Mulch is some kind of organic matter covering above the level of the soil itself. Soil is composed of organic and inorganic matter such as clay, silt, sand, decomposed organic matter, animal manure, plant roots, and micro-organisms such as bacteria, virus, fungi, protozoa, and other tiny organisms. Its texture depends on the ratios of those elements. Mulch is a separate layer sitting on top of the soil providing many things for the living organisms in this rich microcosmic eco system.
Mulch provides many benefits.
1. It covers the soil so the moisture is protected from evaporation. This is particularly important in drought areas, but also any place where it’s hot, especially in summer, where you would otherwise need to water. It also means in container gardens, the amount of evaporation tends to be higher than in the ground requiring more frequent watering. So, an inch of fine mulch can save a lot of watering and the cost of it, as well as the time it takes.
2. Mulch adds fertility to the soil. I am particularly fond of grass clippings caught in a lawn mower over a lawn that is never sprayed with chemicals. The green manure breaks down and adds nitrogen to the soil. But any mulch decomposes and adds to the water holding and nutrition levels of the soil.
3. Mulch provides food for worms. Worms come up to the surface leaving a little channel for oxygen to reach the roots, giving moisture a channel down to them as well, and leave a trail of beneficial micro-organisms which help to break down organic matter into a form the roots can absorb. Also those micro-organisms break down inorganic matter like minerals into a form which the roots can intake.
4. Mulch over time becomes soil by the action of the micro-organisms and the worms, which replaces the organic matter lost through the plant eating what’s in the soil, converting it into the leaves and stems, as well as the fruit of the plant. It needs those sugars, minerals, enzymes and other nutrients provided by organic matter breaking down. Especially important is the fungi which transports nutrients much further through the soil than the roots can reach. Fungi breaks down mulch and organic matter, and even moves it from plant to plant.
5. Mulch acts as insulation for heat and cold. A couple of inches of mulch chosen for the specific use area it goes to, can bring the soil temperature down to one acceptable for the delicate rootlets of a plant in hot weather, or up above freezing in winter. For trees particularly, a foot of coarse wood chips can save a plant when the weather goes colder than the zone it was meant for. I lost 5 trees two years ago when our Zone 7B weather withstood 60 hours of 5 degrees – two zones colder than the trees were meant to survive in. The next year even with newly planted trees, because I mulched adequately, I lost none.
6. Mulch harbors thousands of kinds of fungi which by providing the right kind of material, particularly wood chips but any not-broken-down organic matter, act to foster the growing of the mycelium (strands of fungi which is the body of the mushroom, the mushroom being the fruit) and the breaking down of long sequestered nutrients in a tree’s wood into digestible form. 80% of the volume mass of beneficial micro-organisms is fungi.
7. Adequate mulch will suppress the germination and growing of weeds. Since weeds grow particularly well in disturbed soil, such as if it is tilled, or cultivated, making sure you have at least an inch of cover over the open soil ensures that the weed seeds aren’t activated or if they are, they don’t get any sun to help them grow.
8. Mulched soil tends to be lighter and less compacted making weed pulling, when the odd weed does grow, much easier. The texture difference between well mulched soil and sun pounded compacted soil is amazing and having light soil is so much less energy demanding in maintenance. It holds onto moisture so much better and the roots of weeds just don’t get as much purchase making pulling difficult. If you have to cultivate your beds often, you aren’t using enough mulch. Even using path mulch cuts down dramatically in the amount of weeding necessary and the need for watering.
But all mulches are not equal.
Commercial ornamental dyed or otherwise chemicalized mulch found in landscape and nursery shelves to my way of thinking is just about useless for the growing of food or other consumables. It might look pretty and neat, but it carries with it a lot of stuff the soil can’t use and many of them are toxic. If you’re growing food you don’t want your plants to be drawing in toxic chemicals because you are going to eat that stuff.
I use many kinds of mulch.
Around the little newly planted seedlings in my garden I use the softest finest mulch. I love freshly mowed grass or dried grass fluffy and easy to spread around the delicate little plants. But if I have dry garden waste to chip, that makes a lovely top dressing for annual vegetables.
Around trees, I like coarse wood chips. About once a year I also spread composted manure around each tree, especially those bearing fruit. I also will spread a one inch layer of un-composted chicken coop bedding with wood shavings and chickipoo, but I don’t dig this into the soil around the trees or anywhere because until it decomposes for about 6 months, it is too high in nitrogen/ammonia and will burn the roots. But sitting on the surface and not dug into the soil, it will gradually leach nitrogen and other nutrients in as it rains or is watered, in a slow manner. (I also make manure tea, dilute it, and use that as a liquid fertilizer but always I love manures.)
The manures that have to be composted are cow, horse, chicken, or other fowl. Those that are not hot and can be used as-is are rabbit, goat, and sheep.
As a season progresses, depending on the weather conditions including rain, heat, wind, etc., more mulch may be needed. It breaks down, worms eat it up and mix it in. I have a big chipper and fine chip all the organic waste from the garden. I keep them separate depending on how coarse they come out of the chipper and how easily they will decompose. In fall I chip up corn stalks, tomato vines, dead plants except moist squash vines, autumn leaves, the stems from processed herbs, and any dried organic matter of a fine nature. This is the best for around tender new plants.
I also prune hedges, and in the general progression of a garden various woody branches from trees and they get chipped. These tend to be more of a coarse nature. This kind of mulch is better for around perennial plants such as bushes, perennial flowers, orchard trees and herbs which don’t get replanted often like annual vegetables do. This type of mulch lasts longer on the beds but provides protection for the soil.
Usually perennial beds get a yearly ‘sheet mulching’ (layers of organic and inorganic matter which builds soil) of some inorganic matter like crushed granite for the minerals for the gizzards of the worms (which is used to grind up the organic matter as they eat their way thru the soil), some compost or partially composted manure, and some top mulch. If the soil has shrunk considerably, I may add a few inches of new top soil in newly planted areas, then top mulch that.
I use wood chips as path mulch. For this I like the coarsest type of wood chips. I get them from our local electric company generated from their maintenance of electric lines through the forested areas and to keep the lines clear of trees in general. They even deliver them to us. The mulch on these paths needs to be recharged about every other year. But I notice that if I dig down a few inches below the surface, the soil below that is lush black top soil after a few years.
So, sometimes, before recharging those paths, I will dig up the old mulch base, sift out the larger chips, and take that beautiful loamy soil and use it on my beds to recharge the soil level. The chips come from pretty remote clean areas so I don’t worry about toxins like I would if the trees being chipped were from heavily populated areas or near industrial sites. Trees can collect and intensify toxic materials like heavy metals and petrochemicals if exposed to them over time.
Compost is probably the nicest kind of mulch for vegetable gardens but only the kind I make myself because I know what is in it. Be very alert to the source of any commercial compost as many of those companies add sludge from municipal sources which are absolutely loaded with toxic matter. It must be from a known source. Do your research. If you know a farmer who grows organically, that would be a good source as long as he isn’t also using industrial sludge sources for his own fertilizing.
Another favorite kind of mulch I have used successfully in the past both in pathways and around fairly mature annual plants is straw. Not hay which is basically cut from fields of grasses and wild weeds. Hay is loaded usually with weed seeds and will cause you a lot of extra work. Straw from wheat must be checked out too because farmers are now using Round-Up on non-GMO wheat fields to speed the drying of the grains. Some rice straw is contaminated. But uncontaminated straw from most grains makes great mulch.
Also be wary of hay or straw that comes from fields or pastures where any other herbicide, pesticide or other chemical is sprayed as part of the farmers routine. “Grazon” or similar pre-emergent or pasture herbicide sprays on pastures will knock out your carefully grown broad leaf vegetables such as lettuces and cabbage family. There are some herbicides which are sprayed on organic matter, which stay active for 5 years and have wiped out organic garden and farm crops in England and this country. Know your source. It’s a sad commentary on our world when we can’t trust plants because of man’s treatment of them.
But good natural un-sprayed straw and some kinds of hay if harvested before the plants in the field produce seeds, make wonderful mulch. It breaks down beautifully into rich soil, and feeds the plants and worms beautifully. Same goes for untreated or sprayed lawn grass.
Another interesting kind of top treatment – especially when mixed with other kinds of mulch – feed the soil while also acting as mulch. Organically grown alfalfa, whether in hay form or pellets are very good for the soil and worms. But now farmers are growing GMO alfalfa so again, know your source.
Some kinds of horse feed which is untreated makes good mulch such as Timothy grass. I used to go to my local feed store and they would let me sweep out the semi-trailers which brought in bales of horse and other animal feed, because it was loose and required work to clean up. My exchange was to clean them out and get the good organic matter.
Also, stable bedding with horse manure in it, with also included horse urine, can be gathered as well. But be careful in using this if the horse owners regularly worm their animals because this wormer also kills earth worms, which are your friends. I used to gather nicely composted horse manure and bedding from a customer with stables until I realized I never saw any worms.
One time I found loads of worms, happily, but then I wondered why I didn’t find them always, or why my own beds were lacking in worms. When I figured it out, I never went back for horse manure. It was killing my own earth worms. If you find someone with horses who use natural worm medicine like black walnut tincture that doesn’t kill off the natural worms, that would be OK. But do a test first.
Some people who keep sheep, alpaca or other fur bearing animals use the short furs from the legs or head, or anywhere with shorter fibers, as mulch for their gardens. The plants grow up thru the fibers and eventually the fur breaks down into the soil. It forms a kind of blanket on top of the bed which usually is lighter color, reflecting hot sun as well as keeping in moisture and preventing erosion.
I tried this in a small patch of my garden once but I ended up going back to my plant based mulch. However I know gardeners who swear by using this technique. I was given a goodly supply of older alpaca ‘silk’ (so called instead of fur by alpaca growers) to use as mulch, but I found it was so nice I have been spinning it for yarn instead. The little bit that was too short was so miniscule I didn’t bother keeping it. It depends on what you have available.
If you have a large orchard or widely spaced crops, you can also use un-chipped organic matter such as large leaves from growing plants. If you live near an ocean where kelp or other sea weed washes up on shore, this makes phenomenal mulch and fertilizer combined. People grow the plant comfrey which has large leaves and is also incredibly nutrient rich as a ‘chop and drop’ mulch system, which also does double duty as fertilizer and mulch.
When the comfrey plant gets to be four or five feet tall, they take a machete and whack off the leaves, leaving a foot of the plant above ground, up to 3 or 4 times a season, and lay the leaves directly around the trees or fruit bushes. This is particularly good if you have a regular planting of comfrey every 3 or 4 trees or bushes. You just walk along the row and distribute the leaves as they get cut off. No need to use a wheel barrow.
Another form of mass mulching would be the use of un-chipped corn stalks (from non-gmo corn of course) from a harvester, if it doesn’t already spread the leavings back on the field.
I also gather tree leaves from neighboring towns where the inhabitants rake their leaves out to the curb to be picked up by a big vacuum truck, in autumn. I go there with an empty metal garbage can and a supply of contractor black plastic garbage bags, and a couple of leaf rakes which I use like giant chop sticks. I put the bags in the garbage can to support the bag and make it easier to load. Then I take the two leaf rakes and grab big rake loads of leaves and dump them in the bag.
I prefer the ones where the leaves were run through a lawn mower first as they are perfect for mulch – a 25% ‘green’ (grass), and 75% ‘grown (leaves) for composting and mulching. I try to avoid those lawns where the acorns have been falling profusely as they tend to want to become trees in my garden beds, buried by the local squirrels.
If the tree leaves are full sized, I run them through my chipper into very fine bits, perfect for around tiny plants or composting.
Another use for large bags of autumn leaves, if you have a source with enough volume, is to place a circle of the bags around nursery stock or plants or trees you want to protect from winter cold, such as around a container garden, or baby trees recently planted. They act as wonderful wind protection and insulation. Later you can use the contents for mulch and soil building in the next warm season. I always collect as much of this as I can every year, often making 3 or more trips to town filling the back of my mini-van with bags of leaves. Nobody seems to mind me gathering their leaves.
Having enough gathered organic matter is a constant challenge running an organic garden because I don’t use commercial or chemical fertilizers of any kind except manure, or compost tea of my own devising. So, the soil constantly needs a steady supply of outside sources of organic matter. I used to go to juice bars and get bags of their organic waste when living in California, but this area doesn’t have such a place I can get it from, handily.
However, if you are lucky enough to have such an establishment, work out some kind of deal to get their waste because it makes divine mulch as soil builder. I use it under a top mulch as fertilizer and worm food. If you have a large lawn, capture the grass every other mowing and pile it up or bag it for mulch or soil building in ‘sheet mulching’. You want some of the grass clippings to recharge the lawn itself though and feed the worms there.
I also love coffee grounds because it’s excellent worm food, loaded with nitrogen, and makes lovely soil builder, being the perfect texture. Coffee shops will often save their grounds for you if you supply a bucket and pick it up every day. It’s a bit of trouble but boy, coffee grounds make fabulous soil!!! You might have to pick out the coffee filters, but the abundance of nutrients is worth it. Grounds also make excellent food if you have a worm bin.
A word of caution if collecting grass clippings or other organic matter in large volume from an overgrown location. Watch the seed cycle of the plants. Do your collecting before the seeds are formed or you will be cropping weeds instead of what you want to grow. The idea of using mulch is weed suppression not weed growing.
I like to bag up and save organic matter whenever I find it, or whenever I do chipping. I keep separate kinds separated by location so I know which one to use for which purpose. I keep my eyes open for gathering opportunities and have several regular sources from friends or willing contributors. It’s amazing what you can find if you are looking. Then when I need to recharge a growing bed or am creating a new one with sheet mulching I have everything to hand.
A friend recently was building a house and had a big pile of sand which was too much for the project. She encouraged me to bring a bunch of buckets and several friends, and we filled them up. Now that sand is going onto my beds in preparation for winter. Compost from the summer and chicken poop from a friend’s coop is being spread on all the beds for next year, or recharging my winter growing beds. It all gets used.
If you are wondering why you aren’t getting the kind of yield from your garden or farm, just ask yourself where you can get more organic matter and mulch like a wild person because the more you use this technique the better you and your soil will be. Happy plants come from careful and bounteous use of mulch.