Garden for Nutrition Index
Choose background color:

Organic Garden Soil - How to Build Up Nutrients

The greatest source of nitrogen and carbon is the air. Roots will sink more carbon from the air into the soil than anyone could ever hope to haul or work in. Carbon / hydrogen / nitrogen compounds are the energy source for bacteria and tilling exposes these compounds to be oxidized and dissipate. Plants and the soil biology have been sequestering carbon for ages without any human labor. Let nature do the work for you.

Build Soil with No-till
Continuous Mycorrhizal Roots
End of Season Preparation
Soil Mineralization
Best Practices Review
Organic Fertilizer Amendments
Alkaline Plants

Build Soil with No-till:

Examples of no-till succesfully building soil fertilty. When converting pasture, tillage may be necessary the first year to kill perennial roots.

USDA NRCS East National Technology Support Center - undercover farmers
Gabe Brown - farm as ecosystem
NCAT ATTRA - Innovative No-Till: Using Multi-Species Cover Crops
Masanobu Fukuoka - One Straw Revolution
eOrganic - difficulties of no till in cold climates
John Kirkegaard from CSIRO Australia - advanced no-till, carbon sinking needs other nutrients


Grow mulch in place and then roll / knock down or use as living mulch. The soil should not remain without mulch or roots for long or the soil will become compacted. Mulch will increase microbial activity which also stimulates nitrogen uptake. Living mulch of flax, peas, oats, barley, or chickling vetch can be planted ultra early in the spring before weeds can compete.

eOrganic - microbial activity stimulates nitrogen uptake
Azotobacter fixes nitrogen from the atmosphere

Continuous Mycorrhizal Roots:

In your rotation scheme, never leave soil without mycorrhizal roots in it. Good non-food cover crops are fava, vetch, barley, rye, sorghum, velvet bean, sudangrass, sunnhemp, daikon radish, phacelia, agricultural mustard, amaranth, safflower, crambe, pasja, lupin, chickling vetch, etc. Alley crop trees are the ultimate stabilizer and source of mycorrhizal roots. All of this prevents nitrogen leaching, enhances soil biology, fixates nitrogen, increases soil mineralization, and prevents erosion.

USDA - Cover Crops
SARE - Managing Cover Crops
eOrganic - Cover crops to prevent nitrogen leaching
USDA NRCS - Preventing nutrient loss; no-till causes soil stratification

Make sure your crop rotation includes as many deep rooted mycorrhizal plants as possible. This will help break up the soil and bring nutrients up from deep below. Examples: sunflower, flax, okra, hemp, grass family (except corn), beet, turnip, carrot, salsify, parsnip, cowpea, thistle, etc.

Vegetable Root Structure
Grain and Seed Root Structure
Farmer's Bulletin - Root Systems of Field Crops


Encourage the proper BENEFICIAL BACTERIA to fixate nitrogen and suppress harmful organisms in all plant families.



Encourage BENEFICIAL FUNGUS to aid in nutrient absorption, soil mineralization, and suppression of harmful organisms.


End of Season Preparation:

At the end of every growing season, prepare the row crop area so residue does not provide a breeding place for insects and disease.

When using no-till with cover crops, make sure all organic matter is in contact with the soil at the end of the growing season. If growing winter rye, the end of the season will not be until late next spring.

On the other hand, leave beneficial perennial areas standing for beneficial insects to overwinter in around the garden. They tend to overwinter under beneficial perennial areas.



Turn animals into the fall stubble to speed up decomposition.

Animal urine contains much higher levels of nitrogen and potassium than manure. During medieval times, farmers kept livestock inside their crop fields at night and in the winter. Portable shelters and feeding troughs can be used to keep animals on the fields so urine is distributed directly onto the fields. If urine can immediately soak into the soil directly, it prevents nitrogen evaporation.

Oregon State University - Nitrogen, Phosphorus, Potassium in manure and urine
Soils and Soil Fertility - manure and urine

Manure is high in phosphorus. Use dung beetles or poultry to break up and spread manure. Never shovel or haul manure.

USDA - no till, cover crop, animals


Although most research on soil biology and commercial bio-controls are designed to prop up monocultures, this research can be instructive for those who want to take a more holistic approach. Some research even comes close to a holistic approach.

Friendly endophytes
USDA NRCS - Dr. Kris Nichols, soil biology
Deep Green Fest - soil biology
Univ Vermont - beneficial nematodes
Arizona - Non-toxic competitive strains
Academia - bio-control review.
IJCEPR - bio-control review
Regenerative Agriculture

Soil Mineralization:

Organic compounds cannot be absorbed by plants until they are broken down into ionic inorganic forms. This process is called soil mineralization. It is accomplished by plant root exudates, soil micro-organisms, animals included in the rotation, etc.

**** Root exudates:

Plant root exudates consist of compounds which soil bacteria and fungus can feed on such as carbohydrates and fats. Therefore it increases microbial activity. This is why it is so important to buy seeds from stock grown organically, which is selected for natural full root exudate ability. Chemically grown crops are selected for small root systems that absorb shallow chemical nutrients.

eOrganic - soil biology
Advancing Eco Agriculture - root exudates, nutrient balance, switch to fungal
Texas A&M - root exudates
NCBI - root to root communication
The Rhizosphere: Biochemistry and Organic Substance at the Soil-Plant Interface
**** Soil Micro-organisms:

Each layer of micro-organisms breaks down organic matter a little more and releases a little more of the nutrients.

NRCS - soil web
Wikipedia - soil biology
**** Animals:

Animal manure has many compounds that are broken down into ionic absorbable forms. In some cases, animals do a better job of breaking down nutrients than soil mico-organisms.

Manitoba - manure nutrient availability
Digital Commons - manure nutrient availability

Best Practices Review:

The research over time has indicated there are specific practices which are the most effective: diverse mixed hay perennial pasture with animals, partially decomposed wood chip mulch, rotations, no-till with cover crops, etc.

IFPRI - Include animals, good crop rotation, mulch, PH


In the non-winter season, allow cattle and poultry to naturally spread urine and manure on the forage pasture.

Grow deep rooted plants to break up the soil and bring nutrients up from deep below: alfalfa, chicory, sunflower, dandelion, red and sweet clovers, grass family, comfrey, narrow leaved plantain, sow thistle, etc.

Lumbricus terrestris worms will drag organic material underground in perennial beds and pastures from the organic matter on top of the soil.

Univ of Minnesota

Leaves from trees and grass are best left in place to nourish the plants that grew them. Try not to repeatedly rob organic matter from plants that need it.

Encourage dung beetles to spread and bury manure in pastures.

A pasture / row crop rotation is a cost effective and efficient way to increase soil fertiity and suppress disease.

Pasture builds enzyme levels the best
Pasture row crop rotation
Pasture rotation example

Organic Fertilizer Amendments:

Minerals are one of the most important parts of insect and disease control. But, these amendments should be used only as a last resort. Unlock the nutrients you already have with fungus, bacteria, protozoa, amoeba, and PH neutralization that occurs naturally with organic matter. Be sure to test soil before adding any amendments. Adding excess amendments can actually lock up nutrients.

PH scale and mineral availability
Mulders Chart
Wikipedia - fair discussion of different theories
Maine Organic Farmers and Gardeners Association
Penn State
Jerry Brunetti - importance of minerals in plant, animal, and human health

The importance of testing your soil before adding any amendments cannot be emphasized enough. You can easily make things far worse by not knowing exactly what you already have and what you need.

Organic nitrogen tests
Logan Labs - soil testing
Weeds as soil indicators
Book: Test Your Soil With Plants by John Beeby

These are amendments you might be able to source from your farm. If they came from the farm, then adding them back in should be fairly safe.

Nitrogen sources - Blood meal, feathers
       Bacterial fixation from the atmosphere.
       Protozoa also release nitrogen.
       Held in soil by clay or organic matter.
       For leaf growth.
       University of Vermont - organic nitrogen sources
       Univ of Georgia - management of nitrogen
       eOrganic - nitrogen contribution
       LSU - in soil decomposition (C/N <= 24)
       Ohio State - direct incorporation when C/N <= 24
       Biochar loaded with urine slowly releases nitrogen
Phosphorous sources - ground up bone, manure.
        For flower, fruit, seed, and root.
        Held in soil by clay.
        Protozoa, bacteria, and fungi release via mineralization.
        Windward - hammermill for making bone meal
Potassium sources - wood chips
        Trees can absorb potassium more easily than 
        most other plants.
        Used for root growth.
        Saprophytic decay releases potassium which is then
        held in available solution by clay or soil organic matter.
       Potassium solubilizing micro-organisms - saprophytes

These are links discussing amendments you want to think very carefully about before you add them to your soil. You can really mess up your soil by adding these if you do not need them. Or they can just be a complete waste of money. Deep rooted crops can often bring the required minerals up to the surface from much cheaper. These amendments include rock potash, rock phosphate, gypsum, glacial rock powder, kelp meal, oyster shell, granite dust, greensand, pumice, basalt, zeolite, dolomite, etc.

ATTRA - amendments
Glacial Rock Dust
Basalt Rock Powder
Zeolite - Wikipedia
Potash for Organic Growers
Composts and fertilizers
ACERS USA - paramagnetism books - rock dust review and paramagnetism - paramagnetism

Alkaline Plants:

Acid soils are fairly easy to cope with in that most plants will tolerate a certain amount of acidity. And using calcium to reduce acidity is fairly effective and cheap. But alkaline soils are more difficult to deal with. It may be useful to concentrate on plants that are alkaline tolerant until organic matter can be built up. Asparagus, leek, lambsquarters, and dandelion are very alkaline tolerant. Moderately alkaline tolerant annual plants are garlic, beet, sunflower, parsnip, salsify, pea, okra, corn, turnip, pole bean, collard, and kale. Perennials that are alkaline tolerant include pine, oak, honeylocust, currant, daisy, grape, pecan, cherry, chestnut, carob, mulberry, and ginko.

Harvest to Table - extensive list
Royal  Horticultural Society - extensive alkaline tolerant list


In certain situations, composting is better than mulching. But most organic matter is better used as mulch. Mulch increases biodiversity far better than composting. And mulch also helps control weeds longer than compost. Composting can be unsustainable if large amounts of organic matter are pulled from one area to fertilize another area.

"If you smell ammonia, it means you are losing nitrogen"; Dr. Elaine Ingram.

FAO - compost contains mostly thermophiles and airborn microbes.
Dr. Koide - compost is not mycorrhizal
Springer - nitrogen losses during composting can be significant.
Forschungsring - 11 year study of composting shows large losses of nitrogen.
University of Vermont - nitrogen economics
Joel Salatin - animals make the compost
Agriculture 2.0 - carbon footprint
Carbon Footprint
Curtis Stone - does not compost because it is more economic to purchase
List of special materials for mulching and composting:
Hard wood chips - grows a fungus which will kill nematodes.
Willow wood chips - root stimulant
Alfalfa will stimulate growth with octacosanol
          high in silica - strengthens against fungus
Comfrey - cell proliferant
Horseradish greens, garlic, mustard seed
        - suppresses fungus
Thistle - high in silica 
          if allowed to grow to full maturity
          silica strengthens plants against fungus
          allow plants to mature, but not seed, before mowing
Burdock leaf - oligosacharides 
               encourage beneficial bacteria
Stinging nettle - growth stimulant, fungicidal
Colorado State - Nitrate accumulators:
Washington State - Nitrate accumulators:
Sorghums, fescue, johnson grass, pigweed, goldenrod, jimsonweed, mustard, kochia, common mallow, fiddleneck fern, mustards, ragweed, Russian thistle, nightshade, lambs quarters, stinging nettle, elderberry, burdock, bull thistle, and Canadian thistle

MIT - efficient / economic city wide composting
Rodale - recycling necessary to avoid long term mineral deficiencies
PubMed - vertical pipes and large perforation has least nitrogen loss
Washington State University - preservation of nitrogen during bin composting
Garden for Nutrition Index