Hey friends! Welcome back.
So after the first Soil Blog post, I was all excited telling a friend of mine about having started the blog, and how I have a bunch of different ideas, and blah, blah, blah. After I was done, he asked a question “Is soil just dirt, right?”
That little exchange has become the inspiration for this post because like you guys, I want to become a better grower. To do that I think we really have to understand what we are working with, and how any changes we make to our soils will impact plant growth.
In my first post I went on for a bit about soil pH and its impact on bacterial and fungal growth, but I never clearly defined the term soil. Generally speaking, soil contains living organisms (bacteria, fungi, earthworms etc.) and decomposing organic matter while dirt does not. The presence of both living organisms and organic matter are essential for plant growth. Topsoil, or the uppermost outer layer of soil, usually has the most organic matter, and this is where most plants have their roots. In addition to organic matter, soils also contain air, water, and minerals. There are a few soil classification systems that exist to describe different types of soils and dirt. The United States Department of Agriculture (USDA) has 12 different soils classifications, which they describe on their The Twelve Orders of Soil Taxonomy page. Since we all live in different places, our soils will have different classifications, but you should definitely find out what soil types are in your area.
Like soil, dirt can also have air, water, and minerals but without bacteria, fungi, and organic matter, water will not be trapped in the dirt and plants can’t grow. Growers can turn dirt into soil by mixing it with compost, which is just decaying organic matter. Instead of compost, peat moss can also be used. Peat mosses sold in stores are the dried decaying remains of mosses that grow in water-rich environments known as peat bogs. While peat mosses are great for enriching dirt and soils, the harvesting of them is not considered sustainable. These mosses grow incredibly slowly, just a few millimeters per year, so too much peat moss harvesting can have long-term damaging effects on peat bogs.
Another alternative to composting besides peat moss is the use of coconut coir. Coconut coir comes from the inner shell of coconuts, and is produced as a waste product of coconut harvesting making it a renewable and more sustainable soil additive than peat moss. Coconut coir retains more moisture than peat moss, which means the soil will hold water better during plant development. Unlike peat moss, the addition of coconut coir doesn’t necessarily have to make your soil more acidic.
Coconut coir usually comes in three different forms, coco fiber, coco chips (croutons), or coco peat. Coco fiber and coco croutons are longer forms of the coir good for creating space to aerate soil. Since they also hold a large amount of water, they can retain nutrients dissolved in the water further contributing to plant health. By themselves coco fiber or coco croutons are inert, meaning they do not provide nutritional value to plants by themselves. Coco peat is not from a peat bog like peat moss. It’s called coco peat because it is sold in a similar form to peat moss, a dried brick. Coco peat is the ground up form for the coconut coir. This form can be added during composting which adds greater water retention to compost soils. Composts that include coco peat tend to have a lower pH, which is better for some plants. Coconut coir is usually in the pH range of 5.2 to 6.8. This is much closer to neutral than peat moss which has an acidic pH between 3.5 or 4.5. Using a substrate that is closer to neutral has many microbial benefits. One being an increase in microbial diversity, accompanied by a lower pathogenic fungi population. Pathogenic fungi prefer to grow in acidic soil conditions, ideally in a pH range of 3.0-5.0. As a result, this reduces the chances of your plants developing a disease. The fact that coco fiber retains a lot of water can modulate acidity, and is sustainable makes it a great soil additive.
So what do you think? Does coco coir sound like something to try in your garden?