Concerning the Bio-Extensive Market Garden
by Anne & Eric Nordell of Trout Run, PA
Queries from Quebec
Dear Anne and Eric,
I’ve been reading your articles for the last four years or so. I started with back issues of the Canadian Organic Growers Eco-Farm and Garden; then I interned with Ken and Martha Laing at Orchard Hill Farm and discovered a treasure trove of SFJ.
Currently I run a farm with four friends outside of Montreal – La Ferme Cooperative Tourne-Sol (Sunflower Coop Farm in English). We have 8.5 acres in cultivation (of which 1/3 in cover crops). We distribute our vegetables to 185 CSA members and two farmer’s markets. We do not farm with horses (yet); we do have a tractor for ground preparation but a lot of our planting and weeding is done by hand – the wheel hoe is a favorite tool.
Following your example, we trialed ¼ acre under ridges last Spring. We had peas, lettuce, carrots, beets (& more!) in the ground the 3rd week of April (at least two weeks earlier than normal) – we had an amazing market spread weeks before any of the other local growers.
Here are some questions I’ve been left with after reading your articles:
- How much has variety selection played in your success?
- Do you irrigate your house garden? And what kind of rotation do you use in it?
- Do you treat perennial herbs as annuals (or biennials) and then till them in?
This letter is mainly a Thank You for being so generous with all your information; for being so prolific in your writing; and for demonstrating that a small market garden can work.
Les Cedres, Quebec
Wow! Cultivating over 5-½ acres of market garden vegetables with a wheel hoe! We can’t help thinking that a good team of cultivating horses would just slow down the energetic farmers at the Sunflower Cooperative.
We wish we had some of that sunflower power for quickly cultivating by hand Daniel’s wide ranging questions, especially the ones that open up new ground for this column, such as the topics of irrigation and seed varieties. Perhaps it won’t seem like such a long row for us to hoe if we begin by cultivating the more familiar territory of how the perennials and house gardens fit into the bio-extensive rotation.
We treat the short term perennials, including medicinal herbs, oriental lilies and strawberries, as biannuals. We typically establish these perennials in the same fields as the EARLY planted vegetables. The big difference is the EARLY annuals are usually followed by a fall cover crop of rye while the perennials remain in place over winter and through the first half of the following year. Interseeding the perennials with vetch late June of the establishment year and then mulching them with wheat straw over winter, provides similar erosion control and organic matter additions as the rye cover crop following the EARLY vegetables.)
We turn under the short term perennials right after harvest midsummer of the second year. Initiating tillage immediately following peak production allows enough time for a brief bare fallow period to set back the weeds before planting a cover crop of rye and hairy vetch early September in preparation for LATE vegetables in year 3. Treating the perennials as biannuals minimizes the buildup of insects, weeds and disease while keeping the soil restoring, weed depleting aspects of the four year bioextensive rotation on track.
We grow the longer term perennials, including Asiatic lilies, raspberries and many of the culinary herbs, in our house gardens where we have access to irrigation. Because these perennials usually require several growing seasons to reach peak production and their harvest often extends late into the fall, we manage them quite differently than the short term perennials in the unirrigated fields. For example, we usually leave the culinary herbs in the same place in the gardens for several years before moving them to a new location. The slower developing Asiatics and raspberries remain in production even longer, at least five-to-six years before turning them under.
THE HOUSE GARDENS’ ROTATION
The rotation in our two, roughly quarter-acre house gardens is much more flexible than the bio-extensive system used in the fields for a couple of reasons. First, the management of the long term perennials interferes with the normal four year rotation of cover crops and bare fallow periods. Second, now that we have four portable hoophouses (two in each garden), we keep these temporary structures in the same location for two growing seasons before taking them apart and moving them to a new site. That is, we move just two hoophouses each year, alternating between the two gardens.
We generally follow the long term perennials with an extended bare fallow followed by a fall cover crop of rye. The idea is to clean up the perennial weeds, like quackgrass and dandelions, that inevitably get established in these untilled parts of the garden. Really, this is the very same strategy we used to bring the old hay fields into vegetable production during our first years on the farm as described in more detail in the revised booklet and our new DVD (see notice at end of column).
By contrast, the buildup of perennial weeds is usually not much of a problem in the portable hoophouses. Instead, we are more likely to see an increase in high fertility annual weeds after two years of applying compost between each successive crop of intensively planted vegetables. To remedy this weed stimulating situation, we follow the portahoopies with a fast growing, fertility demanding summer cover crop, like sorghum-sudangrass or Japanese millet rather than use an extended bare fallow. These deep rooted, high carbon cover crops rapidly use up the surplus nutrients in the soil, creating a growing environment less conducive to the germination and growth of high fertility weeds.
Although the perennials in the house gardens only require watering during severe drought conditions, irrigation is an ongoing necessity for the annual vegetables grown in the portable hoophouses. Fortunately, the spring which supplies our packing shed, barn and home with water has plenty of reserve for irrigating the portahoopies.
We use those indestructible soaker hoses made from recycled tires for drip irrigation in the hoophouses because they seem like a more sustainable investment than plastic drip tape which must be discarded after just one or two seasons of use. The downside of the soaker hoses is that they distribute moisture unevenly.
This past season we experimented with Queen-Gil drip tape in two of the portahoopies positioned end-to-end in the lower garden. The Queen- Gil tape, with clog-free drippers every four inches, provided much more uniform and efficient soil wetting. We also felt that the added expense of installing a header (which we positioned between the ends of the two hoophouses) plus pressure gauge and filter, was offset by the convenience and flexibility of having a shutoff valve for each drip line where it connects to the header. We really liked this feature for irrigating the portahoopies because the outside beds are often moister than the middle of the hoophouses due to rainfall seeping in from the edge of the structures.
Two drip lines per 36″ bed seems ideal for watering four rows of cutting lettuce, cilantro or dill; three rows of leaf lettuce; two rows of basil, eggplant, swiss chard or kale; or a single row of tomatoes. However, for germinating small seeds we prefer the durable and flexible Andrews sprinkler hose from A.M. Leonard, especially if the soil is bone dry from previous cropping and bed renovation.
We hope that CQ readers will keep in mind that our real expertise is dryland market gardening, not plumbing. Our experience with irrigation is limited to a small fraction of the vegetables that we grow. We recommend anyone serious about setting up field irrigation to get in touch with growers who water most of their crops.
VEGETABLE SEED VARIETIES
Also keep in mind that our 25 years of market gardening has been limited to this small patch of soil in the Allegheny Plateau. The vegetable varieties that we have selected over this time may not be at all appropriate for other climates, soil types, cropping systems or markets.
Although disease resistance, yield, ease-of-harvest and expense are all important considerations for varietal selection, our highest priorities have always been appearance and taste. Without a doubt, eye appeal is what attracts customers to our stand at The Williamsport Outdoor Growers Market, and the exceptional flavor of our produce is what keeps bringing them back week-after-week. Our customers also rave about how long our vegetables keep without spoiling, an attribute, like flavor, which we think has as much to do with our location and bio-extensive system as the bredin characteristics of the vegetable varieties.
Due to the consolidation of the seed industry, many vegetable varieties that we have depended on for years are not always available or have been discontinued altogether. For example, our favorite leek variety, King Richard, has been available sporadically in recent years, and our longtime carrot of choice, Nelson, was not offered anywhere in 2007.
You would think that this precarious situation would be enough incentive for us to start saving our own seed. Unfortunately, many of our tried-and-true choices are hybrids and neither one of us seems to have the time or inclination to make a concerted effort at saving and selecting seeds.
One of the advantages of a cooperative farm arrangement, like the Ferme Cooperative Tourne-Sol, is that the farm partners can be freed up to pursue personal interests like seed saving. In fact, Daniel Brisebois has taken on this project to meet the seed needs of the Sunflower Coop Farm for the past six years. Recently, he has turned seed saving into a sideline business. When he and Emily Broad attended our small group tour in October, he presented us with the coop’s first catalog of organic, open-pollinated seeds for home gardeners. (www.fermetournesol.qc.ca)
COVER CROP SEED COSTS
Zeb Bartels of Reynoldsville, PA asked a question concerning cover crop seeds at the small group tour which we thought fit right in with the vegetable variety discussion. Specifically, he wanted to know what is the ratio between the cost of vegetable seeds and cover crop seeds on our farm? We weren’t prepared to answer that question on-the-spot, but our off-the-top-of-our-heads estimate was $1600 for the vegetables and $400 for the cover crops, a four-to-one ratio.
Going over our seed purchase receipts and field records after the field day, we realized our estimates were a little conservative. We spent $1676.26 on seeds, bulbs, sets, tubers and plants for the 3 ¼ acres in production this past year. The actual cost of cover crop seed planted in 2007 for the entire 6 ½ acres under cultivation came to almost $460 or close to $70 an acre.
Cover crop seed costs for 2007 included rye planted at 150 lbs/acre after the harvest of most of the vegetables ($30/acre); winterkilled cover crop mix of 100 lbs oats and 60 lbs field peas/acre seeded after the summer fallow in preparation for EARLY vegetables ($53.40/acre); an overwintering cover crop mix of 100 lbs rye and 32 lbs hairy vetch per acre established after the summer fallow in preparation for LATE planted vegetables ($84/acre); and single-row interseedings of hairy vetch ($10/acre), buckwheat ($7.40/acre); sorghum-sudangrass ($7.00/acre), and rye ($2.60/ acre) down the middle of the pathways of most of the vegetables.
The last time we reported on cover crop seed prices (see p.64 in the Summer ’99 SFJ) we estimated our average per acre cost for the four year bio-extensive rotation at $40.00. Using that baseline, our cover crop seed costs have increased 75% over the last eight years! We attribute most of the $30.00 increase to the requirement in the federal organic standard to use certified organic seed, including the cover crops. (Untreated conventionally grown seed is permissible if specific varieties are not commercially available.)
For example, prices of organic legume seeds, like clover, vetch and field peas run 50-100% higher than conventional sources. The difference in small grain prices has been even greater for us. We now pay three to five times as much for organic oat and rye seed as we used to spend on these small grains purchased direct from neighboring farmers. And that hefty increase does not even include the extra cost for transportation.
In our minds, the certified organic seed requirement is a prime example of the organic versus sustainable dilemma. On the one hand, the requirement is probably necessary to build up the organic cover crop seed industry and make organic cover crop seed more widely available. Organically grown seed should perform better in a low input, biologically-based farm system than seed produced and selected under conventional management. In addition, many of the organic seed breeders are now offering cover crop varieties with characteristics which can be advantageous for organic farms, such as the four different rust-resistant and/or weed-competitive oat varieties we trialed this past year.
On the other hand, the high price of cover crop seed may be just one more deterrent to farmers using cover crops or going organic. Another hurdle is that the organic cover crop seed industry is still in its infancy resulting in inconsistent quality and availability. On more than one occasion we have had to return cover crop seed due to poor germination or contamination with weed seed, insects or mold.
To avoid this problem we try to purchase blue tag, organic seed whenever possible because it has been state certified for purity. This service usually adds another dollar to the cost of a fifty pound bag, and blue tag seed is not always available when we need it. This means we often have to purchase rye, oats, vetch and peas 6-12 months in advance to make sure we have seed on hand for planting cover crops in early August right after the summer fallow.
To guarantee a reliable supply of weed-free cover crop seed, we should really save our own seed just like the vegetables. Being realistic, we don’t see this critical aspect of long term sustainability falling into place until our small market farm evolves into a diversified cooperative of farmers with varied talents and interests.
As for short term, bottom-line concerns, the increase in cover crop seed prices due to the federal organic requirement has not hurt the financial sustainability of our direct market business. Afterall, the cover crop seed costs represent less than ¾ of a per cent of our gross income from the market garden in 2007. We do not think this is an unreasonable expense, especially when we consider all the benefits provided by the extensive use of cover crops, such as improved soil quality and fertility, enhanced moisture retention, increased biodiversity, reduced inputs and negligible weed pressure. A savings in just seven hours of hand weeding at $10 per hour would offset our average cover crop seed cost of $70 an acre.