Building Soil Health by Dr. Elaine Ingham (PVP096)

“Mother nature abhors bare soil.”Dr. Elaine Ingham


Elaine Ingham Permaculture Voices Project


Key Takeaways:

  • Organic matter holds 10 times its weight in water.
  • Bacterial secretions provide a glue to help hold soil together.
  • 80% of inorganic fertilizers leach out of soil.
  • Look at perennial deep rooted, short plants as cover crops that put more bio-mass in the ground via roots versus above ground bio-mass.
  • Rainfall can compact bare soil.  Keep bare soil surfaces covered.  One option is a biological cover that feeds the microbial soil life.


Source: NRCS

Source: NRCS

SOIL not DIRT – Dr Elaine Ingham talks Soil Microbiology

Connect with Dr. Elaine Ingham:

Soil Food Web

You can contact Dr. Ingham via: soilfoodweb [AT] aol [DOT] com


primer_frontThe Soil Biology Primer by Dr. Elaine Ingham on Amazon

The Soil Biology Primer is an introduction to the living component of soil and how it contributes to agricultural productivity, and air and water quality. The Primer includes units describing the soil food web and its relationship to soil health, and units about bacteria, fungi, protozoa, nematodes, arthropods, and earthworm.


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Comments 11

  1. Great podcast, had to listen to it two times, it was so “nutrient dense”! In her talk, Elaine pointed to a slide of short, perennial cover crops. Any chance of it being posted here?

  2. This is fantastic content!

    Diego, my hat goes off to you.

    Dr. Ingham, you are a the type of scientist the world needs!

    I can’t tell you how much it means to be able to hear explanations of processes that give some real clues as to how to create abundance.

  3. Dr. Elaine Ingham is one of my (very few) heros. Anyone interested in growing plants – or life on Earth – should look up the story of how she stopped the release of a dangerous transgenic bacteria by… a certain infamous chemical company (with a proven record of disregard for human and environmental safely) that has been selling itself as a ‘life sciences’ company.

    A couple points of clarification:
    Herbaceous plants with large biomass above soil can be far more efficient at harvesting sunlight than very low growing plants, as they have more ‘solar panels’ in action. These panels generate the carbohydrates that produced the exudates which feed the soil life. Grasses, in particular, pump massive amounts of carbohydrates into soils. Many kinds of grasses develop very deep root systems; Ingham mentions perennial ryegrass with a root system several feet deep on plants that are just a few months old. Other types of grasses have been recorded with root systems 2 and 3 times that deep, including natives. In other talks, Ingham explains how an anaerobic compaction layer is generally the limiting factor for root depth. (She also covers the importance of distinguishing between truly black anaerobic soil – which is toxic to plants – and the deep, dark rich brown of highly fertile soils (Ingham recommends using a 70% cacao chocolate bar as a guide to the color of these desireable soils – which have long been called ‘black’, causing a lot of confusion. Whether compost or soil, the nose is a reliable guide; if it smells bad, it is NOT healthy soil or compost!))
    A blend of plants is often more effective as a cover crop, particularly as an off-season cover between row crop production, or during fallow years on a rotational system. Not only because different species will thrive in different weather conditions, but because of the synergies that result. Different types of plants, remember, form relationships with different groups of soil life. Diversity = resiliance.
    The key is to avoid creating an anaerobic situation. Grazing the cover crop is one great way to cycle the above-ground bio-mass into the soil, ideally with a mix of livestock species, either co-grazing or in a leader-follower system. For those without livestock, offer a period of grazing to someone nearby who does. Or, allow the plants to mature sufficiently so that the coarser texture of the plants after crimping or mowing keeps the residue fluffly and full of air pockets, and prevents the compaction that results in anaerobic conditions.
    The use of low growing plants (including some the Ingham would likely categorize as ‘weeds’) as living mulch is not a new innovation. 55 years ago, ‘Weeds: Guardians of the Soil’ by Joseph A. Cocannouer was published. Long out of print, it is available at (Many other titles available there of interest to the permaculturally inclinded include ‘Tree Crops’. Please consider a donation to support this e-library making books unavailable or difficult to find elsewhere available for education purposes.) Cocannouer mentions purslane as a beneficial cover crop for corn. This low-growing plant also works well in many gardens – and is delicious! (Sold in many markets around the world, it is sadly given ‘weed’ status in the USA.)
    Another approach is ‘pasture cropping’ as practiced by Colin Seis of Australia. He plants annual row crops into permanant perennial pastures after they have been closely grazed. This is a brilliant use of a ‘cover crop’ that also provides another cash crop via the self-harvesting livestock. And an example of the beneficial use of cover crops that produce high above-ground bio-mass.
    One of the challenges of permaculture is also one of its attractions: the principles remain the same, but the specific details must be ‘tweaked’ to fit our situation and needs – including the context (as Allan Savory would remind us!).

    Kudos, Diego, for doing such a great job on the site and with the conference!! Looking forward to being able to attend one day. (Would love to find an eco-and financially friendly way to get there from the East…)

  4. Hello Diego or anybody else who can help me,
    at 50:15 : “In Dave Jacke’s book there is a table of what the ratio of fungi to bacteria need to be in different kinds of crops. We did about 350 different plant species and that table is in that book. ”

    I assume Elaine refers to the book “Edible Forest Gardens” by Dave Jacke. I could not find such a table in that two volumes.
    But on page 233 of volume one I found the following statement: “The challenge is that though Dr. Ingham has done much work on fungal-bacterial balance, this theory is still controversial. She has so far published little documenting the soil food web preferences of various plants.”

    Does anyone know where I can find this table?
    Any help would be greatly appreciated.

    1. Hello Klaus Roesch,

      Did you ever get confirmation of a list showing ratio of fungi to bacteria need to be in different kinds of crops?

      Thank you,

  5. ‘Building Soil Health’ ends with a call for attendees to experiment with ‘perennial deep rooted, short plants as cover crops . . . ‘ and communicate their results with Dr Ingham. This video was posted on YouTube in 2014. At this later date, have any conclusions become available regarding her request for information?

    I am aware of Dr Ingham’s webpage on ‘Cover Plants’.

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