Phil: In the last video, I was talking about soil mineralization. And in this video, what I want to get in to is, something else that’s very important for soil health and that is organic matter. An organic matter sometimes can refer to something that is living like roots are always growing and living in leaves and plants. But mostly in this context, what I mean is, something that used to be living.
And so that is leaves that are fall into the ground, that is snakes and beetles that are dead and lying on the ground and other animals, it’s microorganisms, it is… all of these fresh things that have recently died and are lying on the ground. Then it’s also the coarse mulch layer if you can kind of see here that is on the ground, which is when these things are starting to be broken down and they’re becoming more like a mulch they’re being broken down by microorganisms.
And then eventually, when we get into the soil, we get in to the humus layer, which is when these things have been broken down and broken down by all these different kinds of microorganisms and it really resist being broken down anymore, it gets into the soil and is called humus. So that’s what we’re going to be talking about today as these forms of organic matter.
The forest excels at recycling organic matter. The leaves from both deciduous and coniferous trees, which is the needles are falling down, whether it would be all in a fall for deciduous or often throughout the year for something it’s coniferous, they’re falling to the ground and they’re being recycled. There are plants and the cannabis underneath, if you get a shot of that, plants that just grow up every year and die back and so that’s a lot of organic matter.
And then underground too, you have the roots that are … as you guys probably know just as big as the upper part of a tree, the roots spread all underground and… hey mosquito, don’t go in my ear. All underground and they actually grow and die back a lot. At microscopic kind of level, they’re always growing and dying and contributing organic matter.
So forest really excels that recycling all these organic matter in to the soil. I should mention, although we don’t have any prairies around us right now, that they create even more organic matter, you might not think so, but because the grasses, the grasses are very dense, they grow up and die every year. They have very dense root systems that grow and die a lot throughout the year.
They create a lot of organic matter and it stays down in the soil, whereas in a forest, a lot of that carbon ends up in the trunk of these trees. But either way, within any kind of natural ecosystem, organic matter is being recycled very efficiently and it’s doing a lot of good work in the soil. And that’s just the plants, so of course there are microorganisms, there are animals, earthworms, insects, all of these are growing and dying and it being recycled back in to the soil too. And but I want to talk about now is the few of the main things that organic matter does for us in the soil, in the forest and in our gardens.
First might be, fertility. Organic matter, especially when it’s gets broken down into more humus in the soil is exceptionally good at holding on to nutrients. So it’s stops nutrients from draining down out beneath where the roots can get them. It holds on to them and it makes them much easier for microorganisms and plants to use it. It chelates with them, makes the much more available to all the other organisms.
And further organic matter is usually composed a lot of nutrition itself. So of course, animals when they die, leaves when they fall, they have some nutrients in them, many different minerals, but especially carbon, which we may not think of as a nutrient, but it’s really one of the most common nutrients that plants need, they made up of largely of carbon. So that’s a very important nutrient for plants to take up, which they partially get from the air as carbon-dioxide, but if there is lots of organic matter in the soil, they’ll be happy to take it from there instead.
Number two is, water and air. Organic matter in the soil especially creates the different spore spaces that allow the soil to hold on to a lot of water, but also bigger spore spaces that allow to hold on to a lot of air. All our roots and our microorganisms need air, so we need that and of course they need water.
And so humus in the soil is good at that, plus the coarse organic leaf layer on the top of the soil is really good at holding on to moisture and air as well. Then there is soil structure, which is partly what I just talked about with the air spaces and the water spaces. But also just the organic matter in the soil is decreases compaction, really helps the soil bounce back from compaction, decreases erosion, it really helps the soil be held together, instead of blowing away.
Then there is providing for soil life and really it’s all the things I’ve just talked about, but organic matter is habitat from microorganisms and earthworms and insects, it’s food, it’s water, it’s air, I mean, it just provides everything that all of the soil food web needs to establish itself and be healthy. And it probably provides other things we don’t know about on an energetic level, helping energy move through the soil. I mean, just really, yeah, creating a community or a soil life can thrive. We found the only sunny spot in this rain course here.
And now what I want to do is, start talking about how we can mimic nature, this rain forest to bring in organic matter into our gardens. And immediately, some of the things we do are fairly un-natural, but they do help us speed up the process of getting organic matter in to our soil and on to our soil. So the first would be composed, composting is not really a natural process, we’re kind of forcing very fast decomposition by bringing organic materials into a certain sized pile or certain amount of water and air and things like that and certain combinations of materials in order to hasten the decomposition of that into organic matter and being on it’s way into humus.
And we might use manure also in our garden, although it’s really best composed first as well. So we bring that composed in to our garden and pretty quickly we have some fairly well broken down organic matter. The next thing is, bringing in a mulch, which is so important for our garden. And the way we do it is way nature does it, which is leaves. Leaves are by far the best mulch. I know that most people aren’t using leaves, but they really are natural their nutrients and they just provide many benefits.
A little bit grass clippings can work too, you don’t want too thick of a layer grass clippings, because it can get anaerobic and promote the wrong kind of microorganisms and they can smell and all that. But a little bit grass clippings is fine and when we don’t have leaves or grass clippings in the short-term, we can use straw, which works really well, doesn’t look quite as natural, but it does fine.
But really, what we hope is that we can eventually get some leaves in to our garden. One thing that you really don’t want to use too much off is bark mulch and wood chips. If you look at the fourth floor here, you don’t see two inches of wood chips or bark mulch that just not … that’s not how it happens. When you see here, mostly leaves, you see some sticks that fall. Hardly any bark, because the trees don’t shed bark all that much.
You see, probably some seeds and some fresh material, but it’s mostly leaves that of course on top, when you get underneath and then they are more broken down. So you can use a little bit of that stuff. Bark mulch tends to, it can cause a nitrogen deficiency in your soil. It’s so high in carbon that I won’t explain that all here, but it can just cause nitrogen to be used up very quickly in your soil.
The same with wood chips and the thing about bark, especially is that how those toxins in it, that’s the plants, first line of defense against insects and other plant feeding organisms. And so there is toxins in bark, especially in coniferous bark that we often use in the garden like fur and seeder, pretty toxic stuff. Now you can use a little bit in an ornamental garden or for example, if you have a seeder edge, sure you could use a little bit of seeder mulch underneath, but you don’t need two inches of it.
If you have a free source of woody material, again in a deciduous like an ornamental garden, that’s a woody garden like shrubs and trees, a little bit can be okay, you might need to supplement some nitrogen, some organic nitrogen, so that you don’t cause soil problems. But really if you had a free source, I’d rather see you composed it for a few years and then bring it in to your garden.
So composts and mulches are great way to quickly bring in organic matters, sometimes we bring it in from offside if we have to, but in the long run, what we really want to do is, mimic nature even more by using for example plants.
If we can plant things that grow quickly and make a lot of leaves that falls and for most of us in autumn, they fall and that’s the great way to create mulch and then naturally it’s going to become more humus overtime. So planting things always making sure we have ground cover is a great way to mimic nature and increase organic matter. Along with that, we really want to have ground covers in our garden. And you can be there, it’s very popular, it’s very popular to use ground covers that are evergreen like IVs, things like that, they can be helpful.
But more I’m thinking deciduous ground covers like clovers and perennials that get recycled into the soil every year and improve the soil when the recycled and also improve the soil, just by being there and covering it and protecting it. And speaking of clovers, if you’re doing a lot of vegetable gardening, where the bed is empty during the early spring and fall, it’s great to plan a cover cop of legumes like clovers and that is they bring nitrogen into the soil, provide a lot of benefits or sometimes grasses are good for or they bring in other benefits, but just always making sure your soil is covered in plants is a great way to make sure that’s always going to get a lot of organic matter.
So you can see how nature gives us a lot of clues as to how to improve organic matter. In the long-term the sustainable way to do it, is to plant a lot of plants that are going to be loosing a lot of leaves and making a nice mulch for you, having cover crops on the ground all the time, just always under social cover is a good way to do it. And then in the short-term, we might bring in some composed and some leaf mulch, some straw mulch to get that organic matter happening much more quickly.
So that’s really important. Step number two is organic matter. It does allow for our garden. In the next video, I’m going to get in to the third step to building a healthy garden ecosystem. As for all the things I talked about today, I do get in to them in much more detail in the academy in my on-line gardening course, so mulching and composting and cover cropping, all of that in a lot more detail. As I mentioned a couple of days ago, the price is going to be going up on Monday night, so if you’re interested in that you might want to have a look at that right now.
In the last post I talked about improving soil mineralization.
Now I want to discuss another aspect of organic soil health that is important for so many things: organic matter in soil.
Organic matter refers partially to living things like roots and fungi, but in this context it mostly means everything that used to be alive.
That means fresh fallen leaves and recently deceased snakes and beetles, to the coarse mulch layer when these things are partially decomposed, to the very stable humus when they’re fully broken down which stays around in the soil for years.
Creating organic matter in soil is something the forest excels at because it recycles everything – all of the leaves (deciduous and coniferous) eventually fall to the ground, becoming mulch and then soil organic matter and then humus.
Whole plants grow up and die back annually and contribute to this. Roots constantly grow and die back, becoming soil organic matter, too.
I should mention, while the forest is a good recycler, prairies actually create much more organic matter in soil because grasses have substantially more root mass and die back almost entirely every year, whereas trees just drop leaves and end up housing a lot of that carbon in their trunks.
But wherever you are in nature, plant recycling is happening.
Then there are the kingdoms other than plants – animals and microorganisms are recycled back into the soil when they die, and even as they’re living and leaving excrement wherever they go. It’s all recycled.
And then it goes to work. Organic matter in soil is important for so many reasons, such as:
- Fertility. Organic matter holds onto nutrients, stopping them from draining out of the soil, and making them easier for microorganisms and plants to use. Plus, organic matter is composed of many nutrients and other nutritional substances itself, especially carbon which is a primary plant nutrient.
- Water/Air. Just like with nutrients, organic matter holds onto water, stopping it from draining out of the soil. It also facilitates bigger pore spaces that hold onto air, which soil organisms and plant roots need just like us.
- Structure. It helps give organic soil a nice tilth, a nice structure. That’s what allows it to hold the right amount of water and air as mentioned above, but also contributes to decreased compaction and erosion.
- Soil Life. Organic matter provides homes for soil life, mostly because of all of the above points. Organic matter is food, water, air and habitat. It probably has many important functions for energy movement in the soil, too.
So how do we mimic nature to improve soil organic matter? Well we often do some things that are admittedly somewhat unnatural but nonetheless helpful, especially if we’re starting a new garden.
For example, we may bring in some compost, which is basically made by forcing organic matter to break down very quickly so we can work it into the soil for the many benefits it brings. We may also bring in some manure, although that is best composted first.
On the soil surface, we want to provide a mulch just the way nature does it. Leaves are the best, and a small amount of grass clippings are okay, too. When we don’t have leaves, we may bring in straw as a reasonable replacement for now, although we hope to get leaves in the future.
When you look in the forest, what you won’t find is 2 inches of bark and wood chip mulch. Although popular in the garden, these mulches really aren’t ideal. They can cause nitrogen shortages in the soil and most bark contains toxins, especially the coniferous barks like cedar and fir that are commonly used.
It can certainly be used sparingly in an ornamental garden, but let’s just be clear that it’s not how nature does it. In the forest, there are some sticks and seeds and mostly leaves in various stages of decomposition.
So composts and mulches are ways to quickly bring organic matter in soil, but we can also get even closer to the way nature does it, through our plants themselves.
When designing your garden, it’s a good idea to use some plants that create lots of mulch. That means plants that grow quickly and create a lot of leaves which (for most of us) they drop in the fall.
It also means planting densely and using ground covers. Many groundcovers are deciduous evergreens, and they can still improve the soil, but I’m especially thinking about clovers and perennials that are at home in a more natural garden design or an orchard.
Speaking of clover, in the vegetable garden we use cover crops during the off season to enrich and protect the soil. Clovers and vetches are legumes that bring in nitrogen, while grasses and other covers provide other benefits. Even allowing certain weeds to grow in your garden will improve the soil.
So you can see how nature gives us some good tips on how to improve soil organic matter. Mulch-making plants and cover crops are the long-term, sustainable way of doing this, while bringing in compost and leaves are a way to ramp things up quickly.
In the next video, I’ll discuss the third factor of establishing a healthy soil ecosystem.