The goal of this project is to lower the barriers of adopting reduced till and no till planting of mid-season vegetables.
There is a great interest in reduced tillage amongst many organic farmers. Farmers are aware of the disadvantages of tillage but still have great apprehension towards adopting no-till planting of vegetables. The fear is since existing weed control equipment cannot deal with the plant mass, a crop can be lost once it is planted in a cover crop. Some “successful” examples use winter rye as a cover crop since this provides the best weed control, but this system reduces the yield of the vegetables to such extent that adopting this practice is counter-productive. Using leguminous cover crops for no till planting of vegetables provides a much better C:N ratio to ensure good yields but also breaks down before the crop can provide a good canopy.
My assumption is that if it works for cabbage it will work for sweet-corn, squash, and other brassicas. There is not a great deal of information available on the “how to incorporate this practice” and what tools need to be adopted to make it work. I want to generate some of that information.
- a) Organic vegetable crop production is hard on the Aside from disrupting aggregate stability, frequent tillage depletes organic matter and disrupts soil biology. Planting vegetables directly in cover crops can offset these negative consequences. Vegetable plants grown in this healthier soil could, in turn, be healthier as well.
- b) Organic vegetable crop production is hampered by high costs of weed Providing shade and cover can minimize weed control inputs leading to lower production cost.
- c) Naturally present fungi in the soil that serve as a filter and hold plant nutrients are disrupted by frequent tillage leading to the loss of plant nutrient which in turn will contribute to the contamination of ground and surface Reduced tillage promotes soil fungi, which promotes improved water quality.
- d) Organic vegetable farmers often use high inputs of compost (often animal based) to offset OM losses and maintain In order to optimize N for yield other nutrients like P and K are over applied. This can in the long-term lead to micro nutrient deficiency and water contamination. The use of leguminous cover crops provides N fertilization without the need of high compost inputs while lowering production costs
I was part of the DACUM work group on reduced tillage in 2015 which provided me with the opportunity to network with farmers leading this work in the Northeast. What was striking was the lack of success amongst these farmers to obtain optimum yield under no till conditions (with the exception of green beans). This led me to experiment with leguminous cover crops. After one
successful year of using a variety of leguminous cover crops, I was able to select hairy vetch as the ideal cover crop for both N fixation and soil cover. But as hairy vetch does not provide the ideal biomass for farmers in the northeast, I realized that some cereal should be mixed in to obtain the necessary 4000 lbs of biomass (rolled vetch is about 2500 lbs of biomass) and increase the C/N ratio from 12 to about 25. Triticale was selected as companion of vetch as its maturation (anthesis point) falls around the same time when vetch can be rolled and crimped. What we do not yet know is what the exact seeding rates should be, or how these mixes perform in different years.
Recent work with tillage radish for early-season, no-till spinach looks very promising (LNE-11-312). Project manager Lounsbury notes that this is not a good fit when planting brassicas, and of course this cover crop doesn’t provide any nitrogen. However, this work certainly provides one piece of the no-till puzzle. Most of the other work with no-till or reduced-till vegetables uses permanent raised beds. Jay and Polly Armor have been using permanent beds for up to 17 years (http://www.mofga.org/Publications/The-Maine-Organic-Farmer-Gardener/Summer-2014/No-Till), and other locations such as Tobacco Road Farm are using similar systems (https://thenaturalfarmer.org/article/no-till-vegetables-at-tobacco-road-farm/). For small-scale growers, permanent beds seem to be an ideal option. However, larger-scale growers often cannot utilize these same approaches.
My experience in the 2015 DACUM group hosted by Dr. Anusaya Rangarajan and Bryan Caldwell indicated that many organic growers have tried to plant directly into an organically killed cover crop, but there have been no notable success stories in the US. Jan-Hendrick Cropp, a German farmer who I collaborated with while working at the Farm Hub, has been more successful than we have at developing systems of planting into a cover-crop, but he relies heavily on “transfer mulching” to make up for the lack of biomass needed for good weed control. Transfer mulching involves moving chopped green hay or cover crop from one field and drop spreading it into another. This is prohibitive for almost all vegetable farmers, who do not have this sophisticated equipment and likely cannot afford to purchase it for this purpose. His work can be viewed here: https://articles.extension.org/pages/71822/rotational-no-till-and-mulching-systems-for-organic-vegetable-farms-webinar
I am a graduate of the Groenhorst College, a biodynamic agriculture school in the Netherlands. I focused my studies on integrated farming operations. I have been a biodynamic/organic farmer since 1985 and founded Roxbury Organic Farm in 1990. I have experimented with cover crops since the beginning of my career. 2014 and 2017 I was employed at the Hudson Valley Farm Hub in Hurley NY. There, I was responsible for the creation of a farmer training program and oversaw the transition to organic and ecological practices of the 1200-acre former sweet corn farm. I have since retired from my work at the Hub as well as from my daily involvement with the Roxbury Farm CSA. Farming is still my only source of income, but In the coming years I will be able to dedicate more of my time to some of the lingering questions I have about how to maintain healthy soil under organic vegetable crop production while producing a limited number of crops.
The soil was tested in May indicating that potassium and phosphorus levels in particular are low while calcium and Magnesium are sufficient to high. This prompted me to order fertilizer in the form of Composted Chicken Manure as well as Potassium Sulfate. For details here is the soil test: SM027211
- The plots were initially subsoiled with a Yeoman plow to break the plow pan, and the fertilizer was incorporated with a rotary tiller. This was followed by repeated disking in order to kill the perennial grasses and weeds in the sod. The idea was to not disturb the soil too deep with horizontal tillage. While the weed pressure might have been lower when a mold board plow was used, the decreased disruption of the substrate below 4 inches was one of the objectives of this trial.
- Composted Chicken Manure in the amount of 1000 lbs per acre was applied as well as 100 lbs of Potassium Sulfate per acre in addition to 60 lbs of woodash. This was incorporated with a Perfecta II Harrow that also created a smooth seedbed.
- Buckwheat was planted on June 27th at 80 lbs. per acre as a weed suppression.
- The Buckwheat was worked under at August 5th with a disk. In order to prepare the ground for triticale and Vetch, one additional pass was needed with the disk .
- Additional fertilizer was applied on August 12 in the form of composted poultry manure in the amount of 1500 lbs per acre and disked in
- Before planting I needed to create a smooth and level seedbed which would help the following year with effective rolling and crimping. A Perfecta II harrow was used three times as the ground originally found in sod proofed to be quite uneven.
- In order to plant the correct amount of triticale and vetch in each plot the grain drill (an old John Deere 930) had to be calibrated. The calibration chart inside the seed box had proven to be accurate for the buckwheat so my hope was that this would indeed work well for the triticale and vetch. Unfortunately as I was planting 20 lbs increments of triticale and vetch the chart did not contain numbers that low. Instead we needed to have a dry run before we would experiment in the field.
- The plots were planted on September 13th and 14th. Each plot was covered 6 times opening and closing the drill as based on the application . The calibration was set on 20 lbs per acre and each plot was seeded in either 20, 40, 60 or 80 lbs of triticale. The following day we emptied out the grain drill and calibrated this for vetch and each plot received either 20 or 40 lbs of vetch.
- Flags were planted in each plot whereby each green flag represents 20 lbs of triticale and each orange flag 20 lbs of vetch. The map was also created in digital format for future reference and in case the flags would disappear over the winter.
- Due to a relatively wet fall the triticale and vetch came up quickly which also promoted plenty of winter annuals like yellow rocket, annual bluegrass and some mustard to germinate.
- While initially the idea was to tineweed for the winter annuals, the hairy vetch would not lend itself for this kind of weed control. If the weeds proof to be an issue in the spring we might need to walk the plots and resort to some hand weeding.
So far I think I have learned that many passes could have been saved with a more aggressive form of primary tillage like a moldboard plow. While I have always used a moldboard plow when I turn a perennial pasture or hayfield back in crops, for the purpose of this trial I was hoping to avoid any form of horizontal tillage. I won’t do this again. Not only was this an issue in creating a final level seedbed, a moldboard plow would have buried the winter annuals on the surface of the sod. In another section of the farm where I used the moldboard plow we saw a different weed profile. While mustard was present there as well, very little grass germinated. I am particularly concerned with the annual grasses becoming an issue in 2020.