At various workshops and meetings I’ve often heard statements along the lines of “no-till approaches are all very well for broadacre cropping (e.g. grain crops), but no one uses them for vegetables” – to the point where I just assumed that there must be good reasons for not doing it.
Can it even be done, even if only by dedicated permaculturists willing to put in huge amounts of effort? Well, yes it can, but not just through huge amounts of manual labour and on a small scale. There are people our there successfully doing mechanised no-till vegetable production. This article by Dr Mark Schonbeck on the Rodale Institute’s website tells the story.According to the article, Dr. Ron Morse, a professor of horticulture at Virginia Tech, in Blacksburg, Virginia has been working for more than two decades on soil-conserving systems for vegetable production. This parallels efforts by Pennsylvania vegetable grower Steve Groff (in an article by Marni Katz) over the same period on his Cedar Meadow farm. The permanent cover cropping system that he has developed helped to eliminate tillage on 175 acres of pumpkins, tomatoes, sweet corn and other vegetable crops on his Cedar Meadow Farm. Not only has this approach reduced cultivation costs and improved yields and quality, it has also helped manage the soil erosion from the farm’s sloping topography.
“You could not pay me to till my land anymore,” Groff says. “Soil erosion has gone from 15 tons per acre, per year, to almost nothing. Organic matter [in the soil] has gone from 2.7 percent 15 years ago to 4.8 percent this year, and yields have improved 10 percent.”
You can find a list of other articles about Steve Groff’s farm here.
Ron Morse (1999#) has attributed the progress and acceptance of no-till vegetable production in the US to advances in no-till planters, development of techniques for managing high residue cover crop mulches and the acceptance of (and improvements to) integrated weed management techniques.
However I think there are a lot of other factors involved, including: farmer attitudes to the “bottom line”, i.e. whether they are mainly profit-focussed or have an eye on the triple bottom line; farmers’ willingness to be different to their peers (i.e. operating outside the norm); and ability and willingness to deal with a different suite of pest problems arising from the use of cover crops.
No-till vegetable farming has been practised in Australia for around 20 years (e.g. Rogers et al. 2004#), but does not seem to have caught on widely. However there was a study of seven trial sites at different latitudes in Australia (including one at Zeibarth’s farm at Laidley in the Lockyer Valley), published in 2006, that also reviewed a range of studies on the application of the approach in Australia. Unfortunately it seems from a quick reading of the report that glyphosate was used to kill the cover crops at most if not all of the sites. However, the report does include an assessment of the use of a combination of Organic Interceptor (a certified organic acceptable herbicide) and flame treatment, but concluded that only glyphosate gave acceptable long-term weed control – though clearly there are farmers in the other articles that I’ve provided links to here who are able to deal with this issue.
You can find a balanced and fairly comprehensive evaluation of the organic no-till approach here and here, providing you with a pretty comprehensive range of considerations to bear in mind when deciding whether to attempt an organic no-till approach to growing vegetables.
One thing to bear in mind though is that a lot of what has been published relates to large-scale vegetable production. People who are looking to produce vegetables for family consumption with a surplus for bartering or giving away will be likely to have a different take on the pluses and minuses of the approach. Steve Groff’s summary might be worth considering:
“… for the grower who does his homework, the no-till system offers significant advantages. No-till growers typically save money by reducing water use in irrigated systems, reducing cultivation equipment and fuel costs and minimizing inputs, such as herbicides and fertilizers.
In addition, Katz quotes Ron Morse who pointed out that growers often realize increased yields through soil moisture conservation and enhanced quality, particularly for crops that lay on the ground. At the same time, there are increased costs in equipment and seed for managing the cover crop.
“A grower has to be really careful to understand the system and do it right,” Morse notes. “It works if you do it right, and there are a lot of advantages.”
# Morse, Ronald D. “No-till vegetable production—its time is now.” HortTechnology 9.3 (1999): 373-379.