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Organic farming is an integrated system of farming based on ecological principles. Whether you're new to farming or are planning to transition from conventional production, there is a steep learning curve. Give yourself plenty of time to learn about building soil fertility and alternative methods for managing weeds and pests. The resources in the sections that follow will help you get started, but be prepared to do lots of reading and talking to organic farmers as you build your confidence and skills.
A GROWING SECTOR
Organic field crop production is growing, and nowhere is that more apparent than in the Canadian Prairies. This region produces close to 80% of all the organic field crops grown in Canada. Key crops include red spring wheat, oats, barley and specialty crops such as hemp. Click here for details about the organic field crops grown in the Prairie.
Organic farming is now backed by credible scientific research and much of this new research is specific to organic field crop production in the Prairie region. Manitoba is home to the Natural Systems Agriculture Laboratory at the University of Manitoba. Organic-conventional field crop comparisons at two locations - Glenlea in the Red River Valley and in Carman in south-central Manitoba, have produced concrete results that organic farmers can use to improve yields and crop quality. 2016 marks the 25th anniversary of the organic-conventional crop rotation at Glenlea. Check out our anniversary video. Click on the link for the Natural Systems Agriculture Laboratory in the Resources section to learn more about this Manitoba organic research.
TRANSITIONING TO ORGANIC FIELD CROP PRODUCTION
Organic Standards require land to rest for 36 months following the application of a substance that is not allowed on the Permitted Substances List. If you can convincingly document that nothing has been sprayed in the past three years, you may be able to shorten the transtion period. However, for crop production you will have to be under the supervision of a Certification Body for a minimum of 15 months.
If you're considering certification, the following steps will help you get started
Step 1: If you live in Manitoba, set up a meeting with a Manitoba Agriculture Organic Specialist.
Step 3: Do some research or take a course. There are lots of resources to help. Gaining Ground: Making a Successful Transition to Organic Farming, a book by Canadian Organic Growers is a great starting point. The Organic Field Crop Handbook also offers good background information along with practical advice for growing organic field crops. A new edition (3rd ed.) is expected Fall 2016.
Step 4: Talk to organic crop producers. You can meet them at local organic events and field days and at organic conferences, such as Organic Connections in Regina (the next one is November 2016), Midwest Organic and Sustainable Education Service (MOSES) Conference in LaCrosse, WI (Feb 23-25, 2017), Prairie Organics: Think Whole Farm February 23-24, 2018 at the Keystone Centre in Brandon. Also, don't forget to check out the organic room at Ag Days 2017.
Step 5: Do some thinking and planning. What can be grown on your land? What was the land used for before? Were synthetic chemicals used? How long ago? You may need to conduct soil testing to determine how much soil organic matter is available and whether your soils are deficient in nutrients and micronutrients.
Step 6: Decide what you want to produce. Do a market survey. Figure out how you will market your products.
Step 7: Find a federally-accredited certification body (CB) to start the certification process. Most CBs have an an online registration form that you can complete in order to receive their certification package. Note that each CB will have different forms and pricing structures. Talk to other organic producers about their experience with a particular CB. Canadian Organic Growers provides has a list of questions that you can ask each CB.
Step 8: Your chosen CB will require you to develop an Organic Plan that includes a carefully-considered crop rotation that will build soil organic matter and fertility and provide needed nutrients to the crop that follows, a plan for managing pests and disease without synthetic chemicals, a record keeping system to document everything that you do, and a farm map that includes potential buffer zones between your farm and the next.
Fertile soil is essential to successful organic crop productions systems. Synthetic fertilizer use is not allowed, therefore organic farmers must use other means to replace nutrients and improve soil fertility. Organic soil management techniques build organic matter and humus, protect the soil from erosion, reduce nutrient loss, and maintain soil in a condition that supports diverse life-forms. Crop rotations are an essential component in fertility management, pest control and long-term sustainability.
There are 17 essential nutrients required for plant growth. The essential macronutrients are nitrogen (N), phosphorus (P), potassium (K) and sulphur (S).Calcium (Ca) and magnesium (Mg) are considered secondary nutrients. Micronutrients include iron (Fe), manganese (Mn), boron (B), molybdenum (Mo), copper (Cu), zinc (Zn), nickel (Ni) and chlorine (Cl).
The remaining nutrients, carbon (C), hydrogen (H), and oxygen (O) compose more than 90% of the dry matter weight of the plant and are supplied from air and water.
Producers in Manitoba usually discover that adequate supplies of N and P are the most challenging nutrients to supply in an organic system, although S can also be a challenge in some soils.
Sources of Nutrients
The primary source of N on an organic farm is atmospheric N fixed by legumes. Forage legumes and plow-down of legume green manure can provide most of the N required to grow crops. Nitrogen s provided to the organic farm through the application of composted manure and by incorporating straw and organic wastes back into the land.
Phosphorus is important in many plant metabolic processes:
Phosphorus is important in stimulating root growth, promoting early maturity, kernel development and increasing winter survival, particularly in perennial legumes.
Manitoba soils Manitoba soils do generally contain sufficient P, but finding P in a form that is readily available to crops can be challenging. Dr. Martin Entz from the University of Manitoba has learned a great deal about managing P in an organic farming system.
Potassium is involved in several plant processes:
The K requirement is high for perennial crops, forages, potatoes and tomatoes. Most of Manitoba’s soils are naturally high I K and can meet the needs of the crop. The exceptions are sandy soils and those with a high organic matter content.
Sources of K include composted manure, but K is soluble and care must be taken to minimize leaching during storage. Much of the K is in livestock urine and will be held in the livestock bedding. Potassium can also be added to the soil in the form of composted straw and hay, powdered basalt, granite dust, clay minerals, langbeinite, greensand (glauconite), kelp meal, wood ashes and a variety of the materials.
Sulphur also has many important roles:
Certain crops such as brassicas and forage legumes require higher levels of S as compared to cereal crops.
The primary sources of S are gypsum (calcium sulphate) and composted manure. Several S-containing soil amendments (such as Epsom salts and langbeinite) may be permitted, but approval from your certification body is required prior to application.
Although composted manure is low in S, it is generally the best amendment since it contains a balanced supply of other nutrients, as well as organic matter and micro-organisms.
Although these nutrients are only required by plants in trace amounts, they are important to plant growth and development, as well as to the livestock that may consume the plants.
In a biologically active soil with good physical properties and a balanced, pH, micronutrients deficiencies are rare. Sandy soils with high pH and low organic matter contents are more likely to have micronutrient deficiencies. Because the range between deficiency and excess is small, certain micros can be toxic to plants if they exceed trace levels. It is therefore recommended that micros not be applied unless a deficiency is confirmed by leaf analysis or by visible plant symptoms. Compost and some seaweed products can supply micros.
Conserving nutrients is an important part of any farm operation. Nutrient loss may harm the environment, in addition to the loss of money, time and resources. For example, nutrients leaching into ground or surface water may cause excessive algae growth and oxygen depletion, harming natural flora and fauna.
Nitrate leaching increases when certain factors exist:
Nutrient run-off increases when certain factors exist:
Nutrient loss can be reduced with effective use of catch crops, crop rotations and good manure management techniques.
Nutrients to meet both the needs of the crop and organic certification standards may be supplied by several management tools:
A green manure is a crop grown primarily for the purpose of being plowed down to add nutrients and organic matter to the soil. Organic farmers consider green manure to be an essential part of the farm ecosystem.
Many field crops can be used as green manure. Legumes such a yellow sweet clover an alfalfa are commonly used but white clover, red clover, peas, Indian Head lentils, black medic and certain vetches are also used to add nitrogen and improve the soil. Non-legumes that perform ad multitude of functions include oats, barley forage grasses, mustard, buckwheat, and fall rye
Green manure plays a role in soil improvement, nutrient management and pest management.
The value of green manure can vary with the amount of biomass, the type of crop and the timing of the plow-down process. For example, most legumes turned under as green manure at the blossom stage will contribute in excess of 100 lb. of nitrogen per acre. A mixture of grass and legumes turned under at the blossom stage will contribute 50-100 lb. or N per acre. Grass and legume residue after harvest will add less than 50 lb. of N per acre. The rate of decomposition also varies with soil and climatic conditions.
Incorporating green manure with a discer into the top 3-4 inches (7.5-10 cm) of soil allows a favourable rate of decomposition. Deeper levels of incorporation will slow down the rate of decomposition. Incorporation levels below 6 inches (15 cm) should be avoided. Tillage in early summer may leave a considerable portion of nitrogen in the nitrate form by winter, and vulnerable to leaching or denitrification losses. Fall tillage will keep N in the organic form over winter, allowing N to mineralize during the next season.
As microbes break down the green manure residue, the micro-and macronutrients from these plants are made available over a number o years. An added bonus is that organic acids are released in the breakdown process, resulting in lower soil pH and increased plant-available phosphorus.
|Table 1. N-fixation in inoculated legumes grown under irrigation in southern Alberta|
|Plant-N derived from the atmosphere|
|Source: R.J. Rennie, Agriculture and Agri-Food Canada Research Station, Lethbridge|
|Table 2. Increase in the available N of Dark Brown soils due to the residue of one grain legume crop|
|Legume||Available N increase (lb/ac)|
|Source: A.E. Slinkard, Crop Development Centre|
When properly inoculated before planting, annual legumes such as peas and lentils will fix 50-90% of the N they require from the air (see Table 1).
Rotating high and low nutrient demand crops
Different crops require different amounts of the various essential nutrients. Rotating high and low nutrient demand crops may avoid depleting one of more of those essential nutrients in the soil. Knowing the nutrient demands of various crops is essential to the producer and many resources are available to provide this information.
Returning crop residues to the soil contributes tremendously to the organic matter and the nutrient pool available for new plant growth. Crop residues also prevent soil erosion and improve the water-holding and infiltration properties of soils (see Figure 2).
The straw from a wheat crop yielding 40 bushels per acre can contain 25 lb. of nitrogen, 9 lb. of phosphorus, 55 lb. of potassium and 5 lb. of sulphur per acre.
Organic producers often use certain commercially-available fertilizer to address specific nutrient deficiencies identified by soil test. Rock phosphate, certain types of elemental sulphur and gypsum, borax, microbial inoculants and other products derived from natural sources are often applied to the soil, to the seed or to the plant as nutrient sources.
Before using an fertility products, check the Organic Inputs Directory to find out which brand name products are acceptable for use, but remember that your Certification Body will have the final say. All measures must be taken to avoid jeopardizing the organic status of the land.
Research by Martin Entz and his students at the University of Manitoba is showing that no-till is possible in organic systems and that no-till methods benefit the soil by increasing soil life, increasing soil carbon content and altering the way nutrients are cycled.
Ways to increase Soil Organic Matter