Why soil quality is important

Submitted by Jeremy on Mon, 10/30/2017 - 00:06

Your neighbor just picked their 5th tomato of the year, and your garden has yet to see any signs of life more than a few green stems. It's the same story, different year and you're worried that you have been wasting your time in a sedimentary lesson in humility.

What is going on and how can you fix it?
An important place to start is the quality of the soil they are growing in. Ask yourself a few questions first:

1. Is this the right soil type for what you're trying to grow? Don't force a plant to grow in soil that it isn't comfortable in. Certain crops like squash or pumpkins prefer compact clay soil, while other veggies like asparagus grow best in spacious conditions. The difference here is in the particle size of the soil, as that has a direct affect on the drainage. Most soils on that you can buy fall somewhere in between the three, and the term for this mix is called a loam.

Loams can be closer to one soil type or the other, leading to prefaces like sandy loam or clay loam. A "textbook" loam soil is 40% sand, 40% silt, and 20% clay. It's important to factor particle size in choosing the soil you will be growing in your garden.

If you'd like to check the particle size your soil has, try performing this simple test.

2. Are the nutrients leached from your soil? Using the same patch of earth year-in year-out will eventually result in the depletion of the necessary nutrients in the soil, namely N (nitrogen), P (phosphorus), and K (potassium). These minerals are the building blocks of plants' life functions and once they are gone, future generations will be noticeably weaker unless these nutrients are replenished.

There are a few ways in which you can maintain soil that is habitable to whatever it is you want to grow.

1. Crop rotation: Growing different crops can help mitigate the loss of nutrients in your soil. Different species use nutrients at different rates, so you can prolong the need to recycle the soil by instead growing something different that year. This process is effective at slowing the depletion of nutrients in the soil.

Legumes are a notable crop that many farmers worldwide will keep in their rotation because on their roots grow a bacteria called Rhizobia. This bacteria takes free nitrogen that is floating around in the atmosphere and creates ammonia, which is shortly thereafter converted to ammonium. When the legume dies, it returns the nitrogenous compounds back to the soil which can then be utilized by following crops in that plot of soil.

2. Fertilizers and composting: In order to restore nutrients back in the soil, adding fertilizer or compost will provide a kick that growing plants need. There are various methods by which these can be applied. Fertilizers can be of organic or synthetic nature.

3. Biochar: A concept that was once mastered by the terra preta people of the amazon rain forest hundreds of years ago, biochar is a simple concept looking to make a big impact on not only the agriculture industry, but on the sequestration of carbon emitted into the atmosphere - one of the leading causes of climate change.

By cooking the biomass in a controlled environment without oxygen, the excess compounds are burned from the biomass, leaving behind pure carbon in the graphite form.

Why can that be a good thing?: Pure carbon is essentially coal, and if you've ever eaten something toxic, you know just how good coal is at soaking up things. Also used in filters of many kinds, the reason why coal soaks up substances is due to its crystal structure. It is often said that with it's cavernous pores and veins, just 1g of biochar has as much surface area as 2 tennis courts. These spaces become storage spaces for nutrients to hide, and microecosystems for fungi and organisms to thrive.

Potted pepper

For more information, check out the International Biochar Initiative's FAQ.