Thursday, January 19, 2012

Sustainable gardening: John Jeavons' biointensive method

In the previous post I discussed the square foot method of gardening. While I found it useful the first few years I was gardening, the space limitations became more frustrating as I wanted to grow more, and more different kinds, of vegetables over a longer season. Along the way I learned about the next method I’ll discuss, the method developed by John Jeavons and the other folks at Ecology Action and described in Jeavons’ book How to Grow More Vegetables Than You Ever Thought Possible on Less Land Than You Can Imagine (the 8th edition is due out next month; I have the 7th edition). It is sometimes called the biointensive method and I will call it that here, but be advised that Jeavons calls it by a longer name that he has service-marked. I don’t know that I can legally use that name, so I’ll call it the biointensive method instead.

Like the square foot method, the biointensive method is based on a three to five foot wide bed so that all of the bed can be reached from one or both sides. Unlike the square foot method, the biointensive method is a whole-system method developed especially for people who have little or no money or access to outside resources to begin a garden. About all that one needs is the desire to garden.  The biointensive method is built on deep soil preparation; composting; intensive planting; companion planting; carbon farming; calorie farming; and open-pollinated seeds. It is all these factors working together that create a sustainable garden or farm, according to Jeavons.

The biointensive method is especially good for people who want to raise substantial amounts of plant foods, foods that offer a lot of calories as well as foods that contain lots of vitamins and minerals. Salad crops and greens offer good nutrition, but little in the way of calories. In order for home-grown plant foods to become a large part of your diet, you’ll need to grow foods with a lot of caloric value: root crops like potatoes or sweet potatoes, grain crops like corn or wheat, and dry beans or peas. The method suggests allocating about 30% of garden space to these crops, compared to about 10% allocated to typical garden crops like lettuce, greens, peppers, tomatoes, carrots, and so forth. Jeavons calls this calorie farming.

Because the method is geared toward people who have little if any access to outside resources like fertilizers to help their gardens grow better and because biointensive practices can quickly deplete the soil if efforts to build soil are neglected, crops that produce compostable material should make up about 60% of the garden area, according to Jeavons. These include grain crops for the compostable stems left behind after the grain has been harvested as well as soil-building legumes like clovers and a few other plants such as comfrey. Jeavons calls this approach carbon farming.

If you can get a soil test done when you begin your garden and have access to organic fertilizers to address any deficiencies, you can add such fertilizers when you begin gardening. If you are growing the recommended space in carbon crops, the only additions to your garden after the first year will be the compost that you make. Making the best compost is thus crucial to keeping a biointensive garden fertile; the book includes directions on making and applying compost in a way that sustains or even increases soil fertility over time.

In biointensive gardening, plantings are made on a triangular grid so that plants are spaced an equal distance from their neighbors. You can see this more clearly in the photo below. Compare the rows in the foreground of this photo to the rows in the middle to see the difference in the way crops are spaced in the two methods.

This allows more plants to be grown in the same area compared to the square-foot method spacings. Biointensive and square-foot gardening share the same advantages of intensive plantings: fewer weeds once the vegetables grow large enough to touch and more economical use of water compared to traditional row gardening.

Companion planting, or planting certain kinds of crops near each other because they have (or at least are thought to have) a beneficial relationship to one another, is also an aspect of the biointensive method but not much discussed in the square foot method. Companion planting can help to draw beneficial insects to your garden, or may use space more efficiently (fast-growing plants placed between slower-growing crops), or plants may act directly on each other, such as nettles increasing the volatile components of other herbs. Conversely, some plants inhibit each other; the book discusses some of this information, or lore, as well so you can avoid these combinations.

In the biointensive method, slightly raised beds are created by the gardener’s own labor and a shovel. Rigorously applying the method means double-digging, or at least getting as close to double-digging as one’s soil allows. While the labor is not beyond the ability of anyone in decent physical shape, it is physical labor and it takes a long time while one is learning the method. Expect at least 8 hours or more of work to dig a 100 square foot bed the first time, maybe the first few times, you do it. It’s best to start with a smaller area at first, say 50 square feet or less, and slowly expand as you learn the method.

You could plant your biointensive garden with seedlings you purchased elsewhere, but what if you can’t afford to buy seedlings or you want a variety not carried as seedlings? What happens if seedlings, or seeds themselves, become unavailable or unaffordable? In order to garden in a truly sustainable way, you need to grow from seed and eventually produce your own seed for future plants. Thus the emphasis on open-pollinated seeds and on growing from seeds in the biointensive method. Jeavons goes further than just explaining how to start seeds: he shows you how to make your own seed flats from scrap wood and how to make your own seed-starting mix from garden soil and compost.

I really like this method because it considers the garden as a whole system and emphasizes making it truly sustainable, for you and for the whole planet. You need very little to begin with it: just yourself, the book, a small area to become your garden, a shovel, some seeds, some compost, and a little organic fertilizer if you have access to it (you can do without the fertilizer, but your yields will be reduced for several years while you are building soil). Because you don’t need wooden frames to outline the beds and you use the soil you already have plus a little organic fertilizer and some compost, this method is much cheaper than the square-foot method for the same amount of garden space and easier to scale up if you want to increase your garden’s size later on. Making and applying your own compost, and growing crops that produce a lot of compostable material, means that this method is not only cheaper but also has the potential of relying entirely on on-site materials to build and maintain soil and grow large amounts of food, a major advantage for anyone with little cash or a desire to garden in a truly sustainable way. The book has excellent tables with all the information you need to plan your garden and evaluate your results, including weights of produce per unit area you can expect to obtain at various levels of experience with the techniques. Once you get good at this method, you will get higher yields per unit area than with square foot or row gardening. Furthermore, the folks at Ecology Action have produced a series of books elaborating on different aspects of the biointensive method, including books on scaling up the method to where it provides all of your food and other items you need (fibers, dye plants, and the like) as well as a (very) modest income from selling high-demand produce. You can spend years engaged in improving your skill with every step of the method!

The biggest disadvantage to this method is that it takes more time to learn to do it well due to its greater complexity compared to square foot gardening. It’s more time-consuming to plant according to triangular spacing, especially at smaller spacings (under 6 inches), than it is to plant according to square-foot spacing. Double digging takes time to learn and time to do, and you need to be in decent shape to do it (please check with a health care professional if you have any doubts about your body’s ability to handle physical labor before you dig your first bed!). It’s more difficult to figure out exactly how many plants you’ll get in a certain area with triangular spacing; in my experience, the charts over-estimate how many plants will fit into a 100 square foot bed at each spacing. It’s more difficult to figure out how to space plants when you are changing spacing for a different crop from one row to the next. The full-sized flat Jeavons recommends is, I think, too large and heavy; stick with a half-sized flat three inches deep. If you are going to grow as many seedlings in flats as the method suggests (certain root crops like carrots, beets, and turnips are started in flats and transplanted, as well as crops like tomatoes that are more typically raised as transplants), you’ll need more than just a windowsill to grow those seeds unless your garden is very small, necessitating grow lights or, preferably, a cold frame. The mathematics involved in calculating numbers of seeds to start, numbers of plants to grow, and yields may be intimating to people not comfortable with basic math; the density of information in the tables may similarly intimate folks who prefer pictures and drawings to numbers. Finally, the small percentage of area allocated to traditional garden crops and the large area that is supposed to be planted to grain crops may not appeal to people who aren’t interested in growing grains and isn’t well suited to people who only have a small space available for gardening.

Jeavons and the other folks at Ecology Action developed the method in coastal California, an ecosystem without much in the way of broad-leaved deciduous trees. Ecology Action advocates the method for other locations that lack such trees. In these cases, I understand the importance of growing large amounts of compostable materials within garden beds; there is little else available to make the amount of compost needed to keep garden soil healthy. Here in the eastern broadleaf forest ecosystem, where every fall carbon rains down on us in the form of leaves whether we like it or not, I wonder if we need to grow as high a percentage of our garden area in carbon crops if we use leaves as a major ingredient in compost. If trees produce more leaves than they need to maintain the fertility of the soil that they draw on, the extra leaves could be used to make compost and the system as a whole remain sustainable. I don’t know if this is the case. What I do know is that the oak leaves that clog our drainage ditch need to be removed for the ditch to work as designed; given that and given that my neighbors don’t like those leaves blowing onto their lawns, I may as well use them as a major ingredient in my compost piles. And if I can use some of the leaves for compost and the whole system remain sustainable, I can plant a higher percentage of my garden to garden and calorie crops compared to grain crops, thereby reducing the extra processing (threshing, winnowing, and grinding) that grain crops require to become edible.

I don’t recommend the full biointensive method to people who want a very small garden (less than 100 square feet) of traditional garden crops, but even if you fall into this category, you may still find Jeavons’ book useful for the excellent charts and detailed information on many different aspects of gardening, especially soil preparation and amounts of compost and organic fertilizer to use. Where the biointensive method really shines is for intermediate-sized home gardens, say anything from a few hundred to a few thousand square feet in size, and for gardeners who want to garden in the most sustainable and the cheapest way possible. While it takes time to learn, the results are worth the time spent. Those of you who learn best by watching someone are advised to obtain copies of Jeavons’ videos from the Ecology Action website as well as the book; I didn’t really get how to double-dig till I watched Jeavons do it. If you’re planning to use square foot spacings but need or want to dig your garden rather than used a framed raised bed, you can use Jeavons’ book and/or videos or Steve Solomon’s book (next post) to learn how to dig your garden.


  1. I'm sold! I think I'll try this out this coming season. Another great post :-)

    By the way, you wrote, "the density of information in the tables may similarly intimate folks who prefer pictures and drawings to numbers". I'm assuming you meant "intimidate", although I like the idea of a chart intimating people who like pictures!

    1. You're correct, I should have said "intimidate." Thanks for catching this!

  2. This was a thorough and well thought out critique of both SFG and GB. I prefer GB due to its comprehensive, sustainable systems approach. It is the lowest cost after you get the spading fork and garden spade, the board for trenching, the organic fertilizers, the compost, the seedling half-trays, etc. GB is still far cheaper than SFG for start up. I would say GB is an order of magnitude cheaper. SFG requires bales and bales of peat moss, coarse vermiculite, etc...basically using fossil fuel imported unsustainable products. GB is truly sustainable...but a bit too complicated to be broadly adopted. It needs to be simplified much more for widespread adoption by real people.