Cultivating Questions: A History and Whole Field Analysis of Field 6 – Cultivating Questions
Cultivating Questions
Concerning the Bioextensive Market Garden
by Anne and Eric Nordell of Trout Run, PA
A HISTORY AND WHOLE FIELD ANALYSIS OF FIELD 6
After the first ten years of cultivating the bio-extensive market garden, we began to see some real differences in the performance of each field. Field 6, in particular, was not a dependable producer. Part of the reason became clear after reviewing our fertility input records and soil test reports: this half-acre plot had not benefited from as much compost as the rest of the market garden, including a stretch of six years when it had not received any fertility inputs at all other than the fallow year cover crops. Needless to say, Field 6 tested low in several key nutrients.
To remedy the situation, we applied a light coat of compost (approximately ten yards/acre) and rock phosphate (500 lbs/acre) for six years in a row. Both the cash crops and cover crops responded with more vigorous, dependable growth, except for two distinct areas where the physical characteristics of the soil were less than desirable.
The east end of Field 6 had always worked tight and hard, making it difficult to turn a full furrow with the walking plow. Not surprisingly, the top-growth of the crops in this area always appeared smaller, especially in dry periods. We assumed this was due to poor moisture absorption and a restricted root system.
By contrast, a poorly drained area in the middle of this field usually produced satisfactory yields in dry weather, but the soil here tended to plow up cloddy, making it difficult to fit a fine enough seedbed for transplants or direct seeded vegetables. From a distance, this part of Field 6 took on a reddish hue as it dried after plowing, resembling the color of our clay subsoil.
Based on these observations, we decided that plowing might be aggravating these problem areas by mixing the thin topsoil with the subsoil and by diluting the soil-enhancing potential of the cover crops and compost throughout the whole plow layer. We had already discontinued deep plowing before planting the cash crops in order to conserve moisture and reduce weed germination, but we had continued to plow in the cover crops as part of our regular fallow year weed management. To see if deep plowing in the fallow year was in fact holding back the development of this texturally challenging piece of land, we made the decision in 1996 to permanently reduce the depth of tillage in Field 6.
Working the cover crops and compost into the surface of the soil during both the cash crop and fallow years improved in short order the drainage and tilth of the wet area in the middle of the field. No more clods to contend with when planting this wet area. And now, from a distance, this poorly drained spot blends right in with the gray-brown color of the rest of the field rather than taking on a reddish hue.
Concentrating the organic matter in the top few inches of the soil also slowly-but-surely improved the moisture absorbing capacity of the east end of 6. After five or six years of this reduced tillage strategy, production at this end of the field began to match the rest of Field 6, even in dry weather. Note the uniform crop growth across the whole field in the photo of mulch-tilled carrots and coles at the end of the dry summer of 2001.
This past year we reduced tillage in Field 6 even further by trying out our ridge-planting system for the first time in on this variable soil. This decision turned out to be a godsend as the ridges made it possible to get our earliest crops in the ground on schedule during a short break in the wet weather. As a consequence, these cool season crops were able to get off to a good start and take full advantage of all the moisture that followed.
To document the performance of Field 6 with hard numbers, we include in this column a whole field analysis of labor and sales in 2003. This budget was developed as part of the NEON research project described in “Counting Beans While Preserving the Grace” in the Summer ’03 SFJ. One incentive for us to do all the mind-numbing record keeping was to add an economic component to the ridge-till/no-till trial we initiated (see the end of the column). Of more general interest may be the way this whole field accounting highlights the relative profitability of some of the crops that we grow.
Please keep the following considerations in mind when evaluating this whole field analysis:
1. The “return on pick and pack” figure is considered by many diversified growers as a quick measure of comparative crop profitability. It should not be confused with a wage or an indicator of net income. For that, a complete enterprise budget, like the ones in last summer’s column, would be necessary.
But given the fact that picking and packing require the bulk of the labor for most market garden crops, this number can be used as fair gauge of how different crops compare and whether they are paying their way. For instance, it is clear from the chart that sweet onions give a much better return on each hour of harvest than scallions, primarily due to all the time required to clean up the small green onions. Nevertheless, we continue to grow scallions to provide our market customers with more variety at the start of the season.
2. Because so many variables affect the “return on pick and pack” number, it is not a very meaningful indicator for comparing different farm systems. For instance, prices usually influence the gross return on picking and packing much more than farm practices (which is why we thought it was important to include the list of retail and wholesale prices for every crop grown in Field 6). Cosmetic standards – we want everything that leaves the farm to look perfectly clean and blemish-free – will also have a large influence on the relationship between harvest labor and income.
Weather can also play a big part in the picking and packing equation. On the one hand, the continuous cool, wet conditions in 2003 really benefited both the quality and quantity of early ridge-till potatoes. Since almost every tuber was marketable, our time spent on sort-out was minimal, which partly explains the very high return on picking and packing this crop.
(Note: the large labor input for row covering the early ridge-tilled potatoes is due to the fact that it includes the time spent picking stones in Field 6 and adjacent fields which we use to secure the edges of the row cover. The payoff is that this practice extends the life of this synthetic material for three to four more years. Besides, it gives us incentive to pick stones!)
On the other hand, the extremely muddy field conditions and damp weather resulted in more time than usual for harvesting, washing and curing many of the crops in Field 6. At times, the ground was so soft that we were forced to dig by hand, and wheelbarrow out of the field, the potatoes and garlic. This single variable explains why the return-on-pick-and-pack number for garlic is so much lower in 2003 than the $42/hour shown in the 2002 NEON enterprise budget despite harvesting similar yields in both years.
3. Focusing the economic analysis entirely on Field 6 may not give an accurate impression of the whole farm financial picture. For instance, the labor for handweeding the early planted crops in Field 6 was much higher than previous years (we handweeded the six rows of no-till garlic in 2002 in 1 hour and 50 minutes compared to the 9 hours in 2003) or other fields in the market garden in 2003 (by comparison, the 2003 crop of mulch-tilled carrots in fields 4, 8 and 10 required no handweeding at all).
The long stretch of moist weather, lasting from the beginning of May until almost the end of June, kept the soil surface continuously moist, and seemed to germinate every last weed in the seedbank. Because our cover crop/summer fallow system has almost completely depleted the seedbank of warm weather weeds, the volunteers we saw in 2003 were mainly cool season weeds, like chickweed, speedwell and violets. For fields planted a month or more later than Field 6, preplant cultivation eliminated this whole generation of cool season weeds, resulting in very low weed pressure for the rest of the season.
As you can see from the photos of Field 6, the cool season weeds were hardly visible and were not a competitive threat to the crops. Nevertheless, we made the extra effort, when it was too wet to do anything else, to remove all of these small, cool season weeds before they could go to seed. In the long run, this “uneconomic” investment in weed management labor should payoff with a reduced seedbank of cool weather weeds, making it much more economical to grow early crops with a minimum of tillage in the future of Field 6.
4. The Field 6 account might also be misleading regarding the total farm income of any given crop. For example, the ridge-till spinach in 6 was the second of many overlapping successive plantings of this crop. Same for the ridge-till peas. The extra-early row of no-till sweet onions and leeks in Field 6 was a first time experiment. Most of these aliums were either no-tilled on the ridges in Field 2 or mulch-tilled in Field 4 a month later. Likewise, the bulk of our potatoes (mainly for storage) were planted into the skimplowed sod in Field 12 the third week of May. Also keep in mind, that many of the important crops in our market mix were not even represented in Field 6, such as leaf lettuce, salad mix, summer squash, culinary herbs, carrots, broccoli, and cut flowers.
To be more straightforward about putting this whole field analysis in a whole farm perspective, it is important to realize that Field 6 represented only onehalf acre out of a total of approximately three and one-half acres in production in 2003. With a gross of over $8,000, it produced more than its share of the total market garden income of $48,500 this past year. Not bad for a field which we could not count on to hold its own ten years ago. And to think, the difference could be attributed to small annual additions of compost and the reduction of tillage to the top few inches of this challenging soil.
