If you have read my blog posts, or my designs, you’ll know that I have been experimenting with small scale grain growing using the Bonfils method. I have been looking at a number of other ways that have been used to grow grain in an attempt to identify what might be the optimum way to grow them on a small scale. What I want to do is to compare the various ways that grain is grown, analyse them, and come up with a series of trials/experiments to identify the key components for a sustainable grain growing system of my own.
Establish Aim and Objectives
Identify the key characteristics of existing Small Scale Grain Growing systems
Compare those systems
Form a research plan to identify suitable trials/experiments.
Form a template for any Permaculture Association Grain Research project.
Although I have described the Bonfils method of small scale grain growing before, this link BONFILS gives a good description, written by Marc Bonfils himself. The key characteristics are planted at 2 feet/60cm spacings, planted into White Clover, with all of the straw returned. The following crop is planted after Summer Solstice, before the preceeding crop is harvested.
The following LINK takes you to a description of Fukuoka’s method written by Larry Korn, who lived with/studied under him. The grain is formed into clay balls and scattered onto a mulch of clover and old straw. The clover is weakened by temporarily flooding of the fields.
SCI is a method of growing wheat on a small scale based on the System of Rice Intensification (SRI). The link takes you to the Wheat page of the Cornell University SRI site. It contains links to articles documenting SRI wheat growing successes. This link is to a recent article describing how farmers in developing countires are increasing their yields using SRI Methods.
The link below is to a PDF file which describes the SCI Wheat Method. It is comprehensive. The key characteristics are pre germination of seeds, planting at 8inch spacings (8 x 12 inch for seed production). Otherwise the growing is conventional.
The Grow Biointensive method of John Jeavons grows wheat in beds spaced at 5 inches, in a triangle, rather than a grid. Other than the spacing, the treatment of the crop is the same as for vegetables, including the use of compost.
There are lots of differences in the way that conventional wheat/grain is grown. The crop is broadcast/drilled, aiming for about 250 plants per square meter, which works out at about 2.5 inch spacing. There is little information about conventional Small Scale Grain Growing.
I am still waiting for books to arrive from India to try and identify anything that might prove useful.
Update October 2012. My reading has thrown up some really useful information on small scale grain growing which has been posted HERE.
The table below provides a brief comparison of the different small scale grain growing systems.
There are a number of obvious differences worthy of trials, or further investigation.
There is a real spread in spacings from just over two inches to twenty four. The most recent evidence comes from SCI wheat, with an 8 inch spacing, 12 x 8inches for seed production. This system has been established for growing in developing countries, which have a higher light intensity than here in the UK. My gut feeling is that if they have gotten their spacings right, a slightly wider spacing would be ideal here, probably in the region of 12 inches. The Bonfils spacing is double that, and gives 1/4 of the total number of plants. What isn’t clear is how much of the wider spacing is to allow the Bonfils technique of sowing the following crop in the gaps between the existing crop before it is harvested.
Following on from the last point in the preceeding parargraph is the question of sowing date. My question here is how significant is the late June sowing date of the Bonfils system? It complicates sowing and harvesting, and if there is little appreciable gain in yield from this early sowing, doing so immediately after harvesting may be a better option. In this instance, it may also allow a reduction in spacing from the Bonfils 24 inches, towards the SCI spacing of 8-12 inches.
Both of the sustainable small scale grain growing systems include an undercrop of White Clover, and the return of all of the straw to the fields. What effect does the clover have on yield, weed suppression, moisture retention/use, and the supply of Nitrogen to the grain crop? My own reading to date has provided mixed results to these questions. Additional questions include whether alternative clovers, or other Nitrogen fixers would be better suited, or whether any should be included at all? Is the return of the wheat straw all that is needed to maintain soil fertility, relying on free living Nitrogen fixing bacteria, rather than those present in plant roots.
Whilst there is some fixation of Nitrogen by clover, this could be replicated by an intercrop such as Broad (Fava) beans, Soy, or French beans. In the Book Farmers of Forty Centuries, FH King describes the practice of growing a Nitrogen fixing intercrop between grains. The layout would be two rows grain, one row beans, two rows grain. With Broad beans fixing more Nitrogen than White Clover, there is a case to be made for leaving out the clover, and growing beans. This would ease weed control, as the weeds could be removed with a hoe. The Broad beans would also add a significant yield of high carbon biomass, provide nectar for bees, and food.
One of the SCI wheat trials compares direct sown wheat with transplants, from a nursery bed, just like rice. The trial showed that the results for direct sowing was much better. It didn’t look at the use of module grown plants, which might be a way to get an earlier sowing, without the need to make space until after the preceeding crop is harvested. Whether the extra work is justified or not depends partially on the result of a trial to see how much benefit a very early sowing might give.
Almost all of the potential experiments that might come about as a result of this analysis will be affected by multiple factors. For example the ideal spacing for plants might change dependant on whether or not a clover, or another intercrop is used.
Further Information Gathering and Analysis
Having looked at the different small scale grain growing methods there are still too many unanswered questions. Before formulating my trials I need to look at some of the research information that is already available. The important parts of that research is recorded below.
This research paper suggests that for wheat a spacing of 7 inches (18cm) gave better yields than a spacing of 14inches (36cm). The wider spacing gave a higher yield of Broad beans. The research was for plants grown in dense rows, not planted on a grid like SCI wheat/Bonfils. What is interesting is that they give an optimum compromise spacing for wheat as 23cm, which is about 9 inches.
This research paper on sowing dates suggests that planting too early leads to excessive tillering, some of which will die back reducing yield. At first glance this would make you think that there is no benefit to early sowing, but if you read the article fully, the reason for the die back is excessive competition. This is for a conventionally grown crop, and there would be nowhere near as much competition from a more widely spaced crop. In the conventional crop the early planting increased tillering, but the competition caused dieback of those tillers. This suggests that early sowing, combined with a wider spacing, may prove to be a good combination to try.
The Use, type, and management of Clover
- This wheat/clover research document says that growing wheat with White clover results in a lower yield than wheat alone, unless the clover is defoliated. If this is done, the yield is higher, with best results obtained by defoliating at stem elongation, and flag leaf stage. The increased Nitrogen makes the grain more suitable for bread making.
- This Clover research document shows that defoliating clover increases the Nitrogen uptake of neighboring plants, increases the root and shoot biomass of the clover, and gives an increased the microbial population.
- This Red Clover research document suggests that the use of Red clover reduces the slug damage to a wheat crop. The article quotes a reduction in yield of the wheat crop, but the first of these clover documents may explain that loss. The clover needs to be defoliated to increase the wheat yield.
- This website provides good information on White Clover, and has links to other cover crop descriptions.
- This newspaper article describes experiments with a Wheat/White Clover intercrop. It suggests that weed suppression and disease protection is enhanced by the clover, but that yield is reduced. Suppression of the clover with chemicals was best for yield, with mechanical suppression less succesful.
- The book Growing Green suggests that both Red and Crimson Clover form better associations with Mycorrhizal Fugi than White Clover. Both also fix more atmospheric Nitrogen.
- This research article looks at the effect of growing an intercrop of Wheat and Broad beans, at six inch spacings between rows, and within the rows. Most of the trial lots showed a net benefit to growing in combination.
- This research paper staes that growing wheat and beans together, at 75% planting density for each crop reduces weeds, and loss of Nitrogen to weeds, whilst increasing overall yield.
- This mycorrhizal fungi research article shows that fungi are able to obtain minerals by dissolving rocks. This is particularly useful in providing Phosphorus.
- This research paper Nitrogen and Phosphorus acquisition by microbes is the best paper on soil fertility that I have read.
- The book Growing Green states that the biggest loss of nutrients is through leaching during the Winter. One of the ways to avoid this is to maintain plant cover all year.
- There is a loss of Nitrogen from White Clover at the onset of Winter. Planting a cereal crop would help to minimise the effects of this and the leaching in the previous point.
- Research carried out by the Rodale Institute suggests that the best way to maintain levels of mycorrhizal fungi in the soil is to maintain all round plant cover, or to replant as soon as possible after any cultivation.
- This research article discusses the importance of soil microbes in mobilising Phosphorous for plant use.
- The Book Soil Fertility and permanent Agriculture suggests that the best way to maintain soil fertiltiy is to return all organic material to the soil, use a small amount of lime to correct excess acidity, and sufficient rock phosphate to replace that removed in crops.
- Phosphorous is the only mineral likely to deplete in most soils.
- Wood Ash contains about 50% calcium carbonate (Lime), 5% Potassium, 1/2% Phosphorous.
Summary of Research and Analysis
Looking at all of the different information presented here, combined with what I already know, I can draw the following conclusions.
- If clover is used, it has to be defoliated, preferably at the right times, in order to avoid reducing grain yields, and enhance the growth of the grain.
- The need to defoliate may affect overall plant or row spacings. Plants too close together will make it difficult to mechanically defoliate.
- Both beans and clover can enhance yields of grain, and suppress weed growth.
- Keeping plants growing at all times will reduce fertility loss through leaching, and maintain mycorrhizal fungi.
- Maintaining or supplementing Phosphorous is critical to maintaining fertility, but too much Phosphorous reduces mycorrhizal association.
- The optimum spacing for grains is not readily apparent, and is a good trial to undertake.
- The importance of the early sowing for the Bonfils method is not supported by any other research that I could find, and is therefore also worth experimenting with.
- If the use of White Clover helps to prevent germination of weed seeds, it casts doubt on the suitability of simply pushing wheat seeds through clover to germinate, as in the Bonfils method.
- I have not seen any research into a grain/bean/clover intercrop.
Identifying the problem
There are two main problems to solve, and both are connected. The first is to find the best way to grow grain. The second is how to maintain or enhance fertility whilst doing so.
Hopkins gives figures for the composition of plants. 90% comes from Carbon Dioxide, and water, 5% from Nitrogen. Therefore 95% of the resources needed for plant growth come free, and are renewable. Only 5% of the material needed for growth comes from the soil. Provided that only the grains are removed, and the remainder of the grain is returned, only a small amount of material/fertility is being lost. If growing crops for sale, this would entail supplementing those minerals lost, principally Phosphorous. When growing for your own consumption, provided that as much effort as possible is made to return those nutrients to the soil, through humanure, or mulch from a WET system, only a tiny amount of fertility is being lost. Phosphorous is technically insoluble in water, but is soluble in a weak acid, such as is created by soil microbes, plant roots, and fungi. That gives three sources of Phosphorous in the rhizosphere.
- Dissolved in the soil water.
- Bound up in plant, animal, and microbial bodies.
- Within the mineral fraction of the soil, sub soil, and bedrock.
Returning the plant material to the soil increases the supply of the second of those sources. We use wood as heating fuel, which is about to increase with the addition of a wood fired cooker. Using the ash in the vegetable growing system is a way of adding some lime, and minerals, gathered from other parts of the property, and then concentrating it. I can also harvest some woody growth as prunings, to compost, or to add directly to the soil, which will have the same effect.
The use of longstraw varieties of grain, and taller plants like broad beans, gives a higher yield of organic matter to return to the soil. This high carbon material should help to provide a significant boost to soil fertility, by providing the fuel for the soil microbes to use to dissolve minerals from the soil, and fix atmospheric Nitrogen. My own observations after just one year of grain growing, is that it yields a significant amount of straw. The straw can be cycled as animal bedding before being returned to the soil, helping to accumulate more nutrients ‘gathered’ by the animals from the wider environment. My own system includes a deep litter chicken house, which is building up nicely, supplemented by twigs, nettles, and other plant wastes.
Deep Rooting Plants
The gathering of minerals is restricted by the reach of roots, or their associated mycorrhizal hyphae. Having observed how deeply chicory, docks, and comfrey roots penetrate, there is an argument in favour of incorporating some into any system. With Red Clover, Sweet Clover, and Alfalfa all being deep rooted, and capable of fixing Nitrogen, all could be included, either as intercrops, or as a separate fertility crop. Chicory, when it starts to produce flowering stalks, changes from soft sappy growth, to a much tougher, carboniferous composition. However I had sown too much, and it needs to be thinned judiciously. Any of the above, when cut and dropped on the surface, bring minerals from deeeper in the soil profile, and deposits them on the top soil, in a form that is easily converted for plant use.
There are two clear trial projects, and a number of variations, that I need to undertake, in order to potentially produce my grain growing system.
- The first is a comparison of different plant spacings to see which spacing gives the best yield.
- The second is to compare the yield of grain from identically spaced plantings, sown at different dates. This is specifically to see if there is a significant benefit to a sowing date earlier than the harvest of the previous year’scrop.
For both of the above, I would like to use a Wild White Clover undersowing initially, but need to identify a good method of defoliating the clover. I had wanted to use chickens, but the volume of vegetable material would be far too high for my egg layers to eat. It might be possible to use a large batch of growers (meat birds), concentrated for a short time, to do the same job, but I don’t eat meat. Use of a hoe would be effective, but this soil miller looks like it could be the answer. As well as cutting the clover off from its roots, the discs will incorporate it into the topsoil, where it will break down more quickly. There is the potential for some damage to the roots of the grain plants. With a wider plant spacing, a push mower could do a better job, but I have yet to find one that would be narrow enough for the sort of spacings that I am likely to be using. It may be possible to use very sharp blades on a wheel hoe, and set them really high. I have seen some good tools used in Asia, such as the finger weeder, but cannot find anybody who wants to send me one.
- The first variations would be to try the first experiment but incorporate a sowing of grain without clover, a sowing with beans and grain, and a sowing with grain beans and clover.
- I would also like to try using red clover as the intercrop.
- With an established bed of White Clover, I would like to compare the germination of grains pushed into the clover, as per the Bonfils method, with a sowing made into the clover after it has been tilled/hoed.
- I still need to consider how to incorporate deep rooted plants, although if the red clover intercrop works well, it may fulfil this role.
- Ultimately I would like to experiment with how much of the straw I could remove from the system, whilst retaining fertility. This might enable me to concentrate any surplus straw on beds that would be growing crops requiring a higher level of fertility, such as corn, or potatoes.
With all of the above I will need to keep detailed records of how much organic material was returned to the beds, what mineral/ash amendments were made, and the yields of each bed.
The late Summer/Autumn 2012 sowing has had to be made before undertaking this design. I have therefore sown/planted out all of my grains at 12 inch spacings, with a sprinkling of White Clover seed around each plant.
This has been useful as it will allow me to grow similar crops in each bed this year, which will help to reduce any potential differences in yield that may be due to the crop grown in 2011/2012. They will all start 2013/2014 following a grain crover crop.
Whilst not directly comparable, I should also get a feeling for whether there is a significant advantage to growing at this spacing, compared with the 24 inch Bonfils spacing used in 2011/2012. I will also get to try out different methods of weakening the clover, and look at how to keep birds and rodents from harvesting significant quantities of my grain
I intend to sow a row of Broad beans down the center of each bed. This is just to see how a three crop bed might function, and to maintain my hardy winter bean experiment. This is experiment two in my Vegetable Grain Design.
My initial plan is to plant identical beds of grains, with only the spacing varied. At the moment I would like to try spacings of 8, 12, and 18 inches, all with an established White Clover ground cover. This would be hoed and incorporated along the planting rows only, with the clover between the rows left untouched. All to be sown at the same time, after the 2012/2013 crop is harvested. All of the grains to be pre germinated like the SCI method.
The second year trials partly depend on the first. If there is a clear ‘winner’ in terms of yield from the first set of trials, I would like to try using that spacing, but with three sowing dates. Late June, late August, and Mid September. The aim of this trial would be to see if there was any significant benefit to the early (Bonfils) sowing of grain into the old crop, before harvesting. Should the 2013/2014 trial not identify an optimum spacing for UK conditions, I would like to repeat the initial experiment to see if the results stay inconclusive. Should it be found that the yield remains fairly constant for all of the spacings, it should be possible to use the widest spacing, which would make the defoliation of the clover, and hand weeding, much easier.
If it is possible to establish an optimimum spacing and planting date, I would like to experiment with the other clovers, and with Broad bean intercrops. However this is some time off, and I am going to leave the details of these trials until I have produced a workable system.
For the initial three years, I want to keep the soil amendments, and quantity of organic material returned to the soil, the same for all of the beds. After this, I would like to maintain a section of the growing space that sticks to a single grain spacing and sowing date, irrespective of what other trials may be going on. I want to use this space to experiment with the types and quantities of soil amendments/additions, that I need to use to maintain fertility. This may depend on what other crops/vegetables may be incorporated into a whole system.
There may be a need for some specialist help/training/eqipment here. Specialist analysis of my soil would be a great tool to see how effective the soil fertility/building is. Sadly, I don’t think that my budget is going to stretch to that. Simple tools to weigh and measure yields of grain, straw, and biomass will also be needed. Some help from somebody competent in making, or modifying tools might help to create a tool capable of defoliating clover in a relatively narrow strip.