Canadian Organic Growers
growing our future
Ideas on Intercropping
By Janine Gibson
DIVERSITY WORKS! FOOD AND COMMODITY PRODUCERS know what a juggling act working with nature can be. Whether designing your first organic crop rotation plan or refining what you’ve been doing for years, intercropping may be helpful in providing guidelines for growing.
The diversity comes with balancing different plant families whose roots occupy different areas in the soil, each taking and giving in their own way. The first step is to know your basic row crop families — legumes, cereals and the broadleaf / brassicas.
One privilege of being an organic farm inspector, is that I have the opportunity to see the often experimental field work of hundreds of organic farmers and gardeners.
I summarized what I’ve seen while doing more than 950 organic inspections in the intercropping chapter of COG’s Organic Field Crop Handbook (2nd Ed).
As farm and garden managers try different approaches to sustain or improve production, inspectors get to listen and watch, reviewing management records as well as touring fields. We see some farmers turning to very old management ideas to help keep their crops and fields healthy in these times of fluctuating weather patterns.
We all do better with community support, and crops are no exception. Different plant families support different families of soil microorganisms.
Avoiding mono-culture does more than discourage pests and weeds — the practice supports a wider community of soil life. A well developed soil food web promotes nutrient cycling and helps soil remain productive even during poor weather conditions.
The types of intercropping you practice will be determined by the type of tools you use: your tools include equipment, your management skills and available labour.
Adjustable equipment is needed for soil preparation and seeding, harvest and seed cleaning, even storage and record keeping. Can you vary your screen settings on your combine so you can collect small seeds like flax along with wheat, or oats and peas together? Farmers slow their cylinder speed when harvesting peas, lentils and beans to reduce damage and splits.
Markets for organic pulse crops require high quality for human consumption. It’s prudent to develop a feed market at the same time to sell the screenings (i.e., damaged and split pulses and grains).
If you like to modify equipment and pay close attention to how slight adjustments affect plant health and crop quality, intercropping is for you. For example, when harvesting intercropped grain and pulses (e.g. lentils, field peas), pulse harvest equipment needs to be set to minimize splitting.
Once harvested, the producer needs to clean the pulse bits out of the grain. This means that the percentage of the dockage will be much higher. To make this financially feasible, it helps to have a feed market for the screenings.
The final tool is your record keeping system. Field activity notes are required for certification and can help you build on your past field work experience. When planning your intercrops, note when your previous peak work periods were, and spread the workload over time.
With the need to protect certified organic crops from genetic pollution, buffers become more important (although the Canadian National Standard for Organic Agriculture does not specify buffer widths). You may be allowed to reduce your buffer if your adjacent neighbours verify that they are not spraying prohibited materials or growing genetically engineered (GE) crops.
Negotiate your buffers with your neighbours and have them sign affidavits (dated, witnessed statements of their practices). That way, if you are strip intercropping with a seeder width of corn, a width of soybeans and a width of wheat, you can harvest in continuous strips right up to your field limit, rather than having to maintain a buffer inside your field margin.
I’ve often thought that the chemical and GE crop users should give up production space and create buffers on their field margins. Not the organic producers!
When seeding two or more crops mixed together, make sure you plan each seeding so that the crops ripen at the same time. If peas or lentils ripen before the oats or wheat, there could be a problem with shattering. As a result, many of the peas that should be harvested may be left in the field and will sprout later.
Buckwheat and peas are both well known for producing volunteers following shattering. Of course, this can have the beneficial effect of inadvertently seeding a green manure crop while harvesting the main crop.
If you enjoy the challenge of keeping a lot of balls in the air at once, and have the available labour and adjustable equipment, you may enjoy the challenges of seeding crops together, some for primary harvest and some for green manure benefits.
The more diverse our farming and gardening operations, the more stability we create, both in our soil ecosystems and in our income streams. Just remember the quote from that strategist Eisenhower: “plans are useless — planning is essential.”
Especially when dealing with diversity!
Janine Gibson has gardened for twenty years and was supported by her grandmother’s garden for the twenty five years before that.
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