Low-Input Vine Crop Production
The goal of this project was to investigate alternative organic production techniques for vine crops – focusing on pumpkins – by using plastic mulch in the rows and different cover crops between the rows.
The pumpkins were planted in mid-May through plastic mulch that was laid in rows ten feet apart. A cool damp period following planting and predation by crows reduced the plant population so spot replanting was done at the end of May. Organic fertilizer was placed around each plant by hand and striped cucumber beetles and squash bugs were hand-picked and killed. In hole weeding was done by hand at the same time. The ground between the plastic was cultivated two times between planting and mid-June when the cover crops treatments of red clover, white clover, buckwheat, and no cover crop were planted.
Spensley reports that the buckwheat cover crop between the rows had the best effect on weed suppression between the rows. It was very vigorous and grew to almost three feet tall. The resulting pumpkin crop from this treatment was superior to those grown in the other treatments. The clovers did not perform well as cover crops. Spensley is unsure of the reason. The treatment with no cover crop had the greatest weed pressure.
Spensley believes that several positive outcomes were achieved from this trial. He showed that a marketable crop could be produced using this system, with less hand weeding and hoeing required than pumpkins grown without plastic mulch and no herbicides. The crop was produced using organic methods; there was no time or materials involved for pesticide applications to control weeds, insects, or diseases; and the soil benefited from the cover crop biomass between the rows.
Negative features of this system included the increased costs of time and materials to purchase, lay, remove, and dispose of plastic mulch; insect damage from striped cucumber beetle may have been economically significant; weed control along the edge of the plastic mulch was difficult to achieve; and he thinks that overall production in this system was lower than that achieved from a system with more insect and disease control.
Spensley believes this model has merit and can be adapted by growers to meet their specific production systems with different row spacing, the use of drip irrigation, and perhaps the use of the plastic mulch during a second cropping year and/or intercropping with an early, short season crop.