Building Healthy Soil by Adding Organic Matter and Loosening It

As we’ve seen, healthy soil is rich, full of organic matter, well-drained, well-loosened, and deep, but how do we create such soil in our garden beds? We add these things ourselves. While rich and full of organic matter or well-drained and well-loosened are not always the same thing in native soils like peats and sands, luckily, in our garden beds, if we loosen the soil and add organic matter deeply, our soil will be rich, full of organic matter, well-drained, well-loosened, and deep—every gardener’s dream.

Adding Organic Matter—An Introduction

Why

The ideal soil for any garden has an organic matter content of five percent. In years past, before heavy agricultural practices pulled so much of it from the soil without returning it and massive amounts of our best topsoils flowed in rivers to the sea, it was much more likely that one would find this level of organic content in one’s soil. Very few garden soils today, however, have that much organic content at the outset. Therefore, we have to add it back.

We add it back because our plants need it. With it they grow big, strong, and healthy, providing us with prodigious amounts of produce and almost completely fending for themselves against pests and diseases. They are at their peak, capable and copious. Without it, they’re a mess, filled with disease, susceptible to pests, and hollow mirages of their possible productive selves.

How

We add organic matter to the soil in our growing beds in three different ways: adding cured compost, applying mulch, and growing cover crops. While some may add more than others, each of these is an integral part of the process of rebuilding the organic matter content of our soil.

Loosening Soil—An Introduction

Perfect soil might be a gardener’s dream, but the soil we find in our own gardens when we first break ground is usually far from this ideal. In reality, most of us start with clay-choked or sand-filled soil—and, almost always, soil that’s in need of considerable loosening and organic matter. We can, however, create perfect soil over time. As green-thumbed gardeners, doing so is our practice—the method to which we devote most of our energy—and the most impactful way we can create strong, healthy plants.

But how?

We use methods that loosen it as we add organic matter.

Why

Most gardeners know that our garden plants really suffer in deeply compacted soil. This is one of our reasons for tilling each season. We till to destroy weeds and turn vegetation into the soil, sure, but we also till to loosen the soil. We all know this intuitively. We’d never plant our vegetables in the garden without first loosening the soil for them. And we definitely wouldn’t plant a row of vegetables directly in the deeply compacted soil of one of last year’s paths without first tilling or otherwise loosening it. We know our plants would really suffer. But why is this? 

Part of the reason loosened soil so clearly benefits our plants is that it makes it TONS easier for their roots to grow out in all directions, gaining increased access to available water and nutrients as they grow. Conversely, think of all of the energy it takes for a plant’s roots to force their way into compacted soil. Imagine roots attempting to grow in soil as compacted as your garden path, or even into some field soils that are almost as hard and compacted as concrete. Their roots are barely able to penetrate these soils, making life and their search for nutrients much more difficult, seriously decreasing their abilities to fend for themselves. But they also fail to reach their full potential in any soil not fully loosened. Truly, our plants only reach their fullest potential when they grow in very well-loosened soil. They become their fullest selves, capable of fending off most insects, diseases, and dry spells simply by having their strongest foundation, their roots, spread out to their fullest extent. 

Another part of the reason loosened soil is so beneficial is that truly healthy soil needs millions of pores—or “air pockets”—for the movement of both air and water. Well-loosened soil has millions of small pockets of space between the soil particles that help with water, nutrient, and air movement.³ The air movement made possible by these pockets of space allows the aerobic microbes characteristic of healthy soils to thrive. Furthermore, not only does water drain better through this well-loosened soil—importantly, making it well-drained, as well—its multitude of small pores provide extra storage spaces for water. Loose soils are also better at keeping water present because of their enhanced facilitation of the upward pull of water through capillary action.

How

There are several important methods: trenching, bastard trenching, double digging, loosening with a digging (spading) fork, tilling and raking or shoveling to shape mounded beds, building raised beds, adding compost on top of killed sod or a cover crop, and simply tilling but keeping beds with paths. Listed in order of required effort, each of these methods brings considerable benefit.

The more labor-intensive methods are the most effective, however, with the most long-term benefits for the widest array of garden plants. In general, the more effort you put forth and the more soil loosening you achieve, the healthier your plants grow. The most intense methods can, however, be a lot of work, especially for a whole garden. For most people, for example, trenching or double digging their entire plot isn’t realistic. The great news is it also isn’t necessary. First, once a gardener is planting in beds, there’s no need to loosen the areas retained for paths. Second, there are only a few garden plants that really need soil loosened to that degree. Some of the less-labor-intensive methods are plenty good for most of our garden crops. Plus, there are some hybrid options that work quite well for many garden plants, especially for their comparatively small amount of work. Let’s explore these methods, starting with the most intensive and productive and then proceeding to increasingly easier, if less effective, methods for many plants. Finally, let’s end our discussion on loosening with an assessment of what methods are most effective for which plants, so we don’t have to put more effort into creating deeply loosened spaces than is necessary for plants that don’t really need it.