Healthy Soil for Healthy Crops

Soil health is the most important aspect of organic food production. If you are just starting out on a new piece of ground that has been strip farmed for years this is going to take some time to accomplish.

I recently attended a soil class given by the NRCS http://soils.usda.gov/sqi  “An introduction to Soil Health and its Role in the 21st Century Agriculture”  The agronomist was talking about the importance of building and maintaining the soil biota. This is not a new concept. This has been going on for years in small scale agriculture. Your grandparents farmed this way mainly due to the limited access to farm equipment technology and soil sciences that prompted higher yield values with less labor. The small scale or subsistence gardener (those who maintained a family garden to off set the grocery costs) had to make due with what was available and inexpensive if not free. This is also why you grandma’s tomatoes had flavor and a few scares on the skin.

What I enjoyed most about the class was the fact that the attendees were mostly district conservationists or DC ‘s, agronomist and soil scientists. These folks were from the Agriculture Research Service ARS and the Natural Resource Conservation Service the very same folks who have been taught by the strip farming agronomists 20 years ago. I however, was the lone wolf certified organic producer in search of more knowledge “from experts” in the field.

What makes for healthy soil

Soil amendments and analysis in organic production

Growing organically in the Sonoran Desert can be a great way to spend your winter season out of the cold in the northern parts of the country.

If you should find yourself down this way and want to start a food plot. One of the most cost saving practices you can employ is a soil analysis by a professional laboratory with a commentary by an agronomist. Our clay or sandy soils are full of salts and sodium. Therefore, knowing the quantities of each in your profile will take the trial and error out of the equation. It will also aid in knowing how much of a certain amendment you will need to add so as to not over buy or supplement something you have plenty of.

Knowing your soil profile will also give you the current Ph, Electro conductivity EC and level of organic material in your soil. EC is the measurement of Electro Conductivity and measures the salts in your soil in ppm or Parts Per Million. A pH is the measure of the acid or alkalinity of your soil measured on a scale of 1-10 with 7 being neutral. Winter produce does well with a soil pH of 5-6. TDS is the measurement of total dissolved solids mainly in your water, but it can be measured in a soil and water mixture. It is best to measure each separately to accurately identify the source.

Taking a soil sample- knowing where to start

This is a relatively easy thing to accomplish and can be done using a 5-point method. You can use a small shovel or a soil probe like the one in the picture. I prefer the soil probe because I can get to the root zone and collect multiple samples quickly for a thorough profile.

Basic probe use:

Soil Probe

Chose a point on your plot area such as the top left corner, place the probe on the ground with both hands on top of the handle and push the  long end into the soil about 6 inches deep and pull out the soil plug. If your soil is hard, you may need to use a twisting or screwing motion to work the probe into the soil.

If you do not have a soil probe, you can use a shovel to dig 6 inches down in the same 5 point areas in your plot. Place a small garden spade of soil in your bucket from each sample point. After you have collected all of the 5 samples and put them in one bucket, mix them thoroughly together. This will give you a general idea of your overall food plot profile.

Locate a soil laboratory in your area by contacting your local nursery, agriculture extension office or Google online for soil labs in your area.

Once you receive the soil sample report, you will know exactly what to add to your soil in order to make it as balanced as possible.  A typical report costs around $60, but well worth avoiding the guesswork.

Bacteria – the Missing Link

Organic material in your soil will help retain water. Microbes such as those found in   Bactifeed will prevent the hardening of the soil forming the caliche you are sure to find.

You can also use hay or compost to add organic material to your soil. I like to use my organic alfalfa by the bale, because I know I am not adding any chemicals that are used by local producers to control weeds and pests. I started building my soil profile a few years ago by planting alfalfa as a cover crop for a few years before I started produce. The use of alfalfa as a starting place is two- fold. First it will help to aerate your soil, because the root system is aggressive and runs deep. The second is that alfalfa is a legume and fixes its own nitrogen, which is a key component in organic production.  Knowing how to amend your soil to get the proper NPK levels is important. NPK is the scientific elemental symbols for N- nitrogen, P- phosphate and K- potassium. These are three key ingredients in soil nutrients that will provide the needed basic building blocks for your plants. So when you hear a salesman ask you if a 4 – 4 – .3 will be sufficient you will know that he is asking is a 4% nitrogen- 4% phosphate- and a .3% potassium NPK value is enough for your application.

How to add Bacteria to Soil

You can give your food plot a boost to help this process along buy introducing a robust culture of microorganisms into your soil by using Bactifeed. It comes in various amounts depending on your application needs. You can apply this by using a lawn sprayer attached to your hose or a Hose On attachment. You can brew this in a large tank if you are applying it to large crop areas by dripping it into your flood irrigation system.

How to have healthy soil in different regions

Developing an ecosphere in your soil takes some time, by tending to the soil in the warmer months. This will enable your soil to remain active in the cooler months as activity slows down. Growing a spring cover crop will help to build your humus and the organic matter needed for the summer planting season. Over wintering will allow your soil to rest and build deep activity which will create better drainage for root development. Here in Arizona we have the ability to farm year round so caring for the soil through crop rotation is the key. Cover crops such as legumes that fix their own nitrogen are a great option and build that soil profile quickly. This will reduce your input costs for next season and will aid in reduction of topsoil loss due to wind and rain runoff.