What Compost Does for the Vegetable Garden

For healthier plants, higher produce yields, and fewer garden diseases, the first place to concentrate on is the soil. Garden soil’s best friend is compost. The first thing gardeners should know about soil is that it’s not dead.

Soil is full of billions and billions of living and breathing organisms that are invisible to the human eye. In the simplest of terms, soil is made up of organic matter, minerals, water, and air. All of these ingredients not only make up a stable medium for roots to hang on to, but also provide for plants’ nutritional needs.

The key to healthy, productive plants is soil that’s rich in organic matter. Organic matter is the very heart of compost, and its final result, humus. Composting is sustainability at its finest for plants and the other living organisms on this planet.

What is Good Garden Soil?

Good garden soil is having as much organic matter in the garden bed as possible. Compost is the finished product of broken-down organic plant and animal matter. In its ‚”finished” form, compost becomes humus. Humus makes complex nutrients in the soil easily available to plants. A soil that’s full of life-sustaining humus is often called “friable,” meaning that it has a full, loamy texture and crumbles easily in your hands. This is what makes excellent soil.

Compost can add any number of nutrients to the soil depending on what materials are added to the compost pile. Other micronutrients that add value to the compost (therefore, the garden soil) are copper, iron, iodine, zinc, manganese, cobalt, boron, and molybdenum. It adds value to soil by providing it with nitrogen, phosphorus, potassium, and other minerals. It can also eliminate the need for synthetic fertilizers and ward off plant diseases.

While humus is the ultimate goal, compost may be used in garden beds at any time during the composting process. For instance, compost at any stage can be used as mulch by retaining moisture, suppressing weeds, and as erosion control.

5 Other Great Reasons to Add Compost to Vegetable Beds

1. Plant Disease Protection – Researchers have discovered another virtue of compost that doesn’t get as much publicity as it should: it’s valuable for plant-disease resistance. The beneficial microorganisms produced by composting organic materials render plant pathogens inactive. Potato blight, powdery mildew, and damping off are all examples of plant diseases that compost can suppress.
2. Composting Extends the Growing Season – Composted soils enable the gardener to plant earlier in the growing season and harvest later in the season. Compost improves average soil structure by bringing it to a loamy, friable state. Nutritionally rich soil with good structure is able to hold heat better than poor soil. For the gardener, this means the soil warms up faster and stays warm longer.
3. Compost Acts as a pH Buffer – For most plants, the most desirable pH is neutral; neither too acidic nor too alkaline. If a gardener is generous with applying compost to garden soil, the gardener doesn’t have to worry about the pH levels as much – if at all. When humus is plentiful in soil, vegetable crops and flower beds are simply less dependent on pH levels in the soil. Due to its biochemical structure, humus acts as a buffer for soils that fall slightly to one side of acidic or alkaline. This not only takes the guesswork out of an average pH level, but in many cases, it can take the pH factor out of the equation entirely.
4. Composting Saves Water – Compost increases soil’s capacity to hold water by a wide margin. For instance, a dry soil low in nutrients may only hold 20 percent of its weight in water. Compare this to a dry soil that’s high in organic content, which can hold up to 200 percent of its weight in water.
5. Composting Reduces Water Run-Off – Due to the poor crumb structure of soil that’s low in organic matter, it can be washed away easily by storms or even everyday watering. Lost topsoil results in even lower fertility, creating a vicious cycle. Compost preserves and enhances soil structure and helps fight erosion, keeping healthy soil under the plants where it belongs.

While synthetic fertilizers may temporarily mask poor soil, they don’t actually solve the problem. They simply mask it. Compost, on the other hand, changes the structure of the soil – making it nutritionally rich.

Interested in reading more about composting? Check out Trench Composting in the Vegetable Garden and How Worms Improve Soil the Vegetable Garden.