Soil Tilth, Soil Structure, and Soil Microbes

The most frequent garden question this time of year is, "when should I plant my potatoes, onions, etc?" My answer, use the Extension Service Year–Round Home Garden Planting Guide. It has a good list of garden plants with recommended planting dates. I also have a document on my web site, where I describe gardening activities, month by month. http://harmonygardens.blogspot.com

I have already started a few hardy things outside, but they are under plastic. In fact, I have some lettuce and spinach that survived in the mini-greenhouse all winter. At this time of year, I have to open up the mini-greenhouse or it gets too hot on the warmer days. The biggest problem with mini-greenhouses in this area is the struggle with the wind.

Planning and record keeping are important aspects of gardening. I do it for two main reasons--to keep up with crop rotations and for keeping detailed records on soil fertilization. I really encourage you to keep up with all fertilizers and compost added to the garden. I also keep records on crop production, and do regular brix testing on the harvested produce.

Soil Tilth. To understand gardening, first and foremost you must understand that what goes on below the surface is the key to production. It's simple cause and effect. The healthy soil is the cause, and the production is the effect. Soil tilth refers to how easy the soil is to work, and is a general indicator of soil structure and health of the soil. Teaming with Microbes, by Jeff Lowenfel and Wayne Lewis is an excellent reference on this subject.

Soil structure refers to how the soil particles are held together, and is a very good indicator of how much life is in the soil. The more life there is in the soil, the better the structure and the better the tilth. Soil life means bacteria, fungi, actinomycetes, earthworms and more. All of these produce sticky carbohydrates that act like glues, binding individual mineral and humic particles together in aggregates. The question of how to improve soil tilth, can be answered in three words. Improve soil life! Here are the do and don't rules in simple and straightforward form:

• Do add compost and compost tea to increase soil organic matter to 5 percent or more, and to add beneficial microbes.
• Do keep the soil covered at all times. Use cover crops and mulches.
  Do keep the soil well aerated. Use raised beds.
  Do remineralize the soil to the proper level to produce nutrient dense produce.
  Don't work the soil excessively. Roto-tilling destroys fungi and soil structure, and reduces the ability of soil to hold water.
  Don't add hostile, toxic compounds to the soil. Avoid chemical fertilizers and pesticides.
  

These rules apply to all kinds of soils – sandy, heavy clays, shallow, deep, rocky, acid, alkaline, anaerobic, humus, unadulterated or virgin, and those where excessive toxins have been used in the past. These rules are essentially the organic gardening methods--the preferred future, sustainability approach.