Developing No-till and Minimum Tillage Pumpkin Production in the Great Plains

Pumpkins are a very popular crop in the Great Plains because they perform well and are profitable for growers through traditional and agritourism markets. However, traditional pumpkin production systems that utilize heavy reliance on mechanical tillage can be detrimental to long-term soil health. One particular challenge in the region is that the incorporation of fall-planted cover crops for pumpkin growers can be difficult due to the short planting/growing period in the fall after pumpkins are harvested. From 2012 to 2014, we conducted replicated trials to investigate the utility of various fall- and spring-planted cover crops for no-till pumpkin systems and compare the top performers with conventional tillage. Duplicate field trials were conducted at the Olathe Horticulture Research and Extension Center (Olathe, KS) and the John C. Pair Horticulture Center (Wichita, KS), which represent the eastern and south central growing regions in Kansas. The treatments included seven different cover crops/mixtures and one conventional tillage treatment. Two of the cover crop treatments were planted in the spring. Plots were treated similar to commercial pumpkin production in the region. At both locations, fall-planted rye/vetch and rye/pea cover crop mixtures performed comparably to the conventional tillage system in regards to total yield. Total pumpkin production using these cover crops ranged from 12.4 to 14.9 tons per acre at the two sites in 2014. In 2013, the spring-planted cover crops had the lowest biomass production of all of the cover crops (P<0.05). The subsequent pumpkin crop experienced the highest weed pressure and lowest yield (P<0.05). Conversely, in the 2014 trial, the spring-planted cover crops had the highest biomass (P<0.05) and performed comparably to the conventional tillage treatment (P=NS). Our data shows that no-till systems can be highly successful when select cover crop mixtures are utilized and the pumpkin crop is managed properly. Although spring cover crops would be useful for growers that are not able plant fall cover crops, our work suggests that their performance is highly dependent on spring weather conditions, as they relate to planting date and subsequent biomass production. Additional trial observations showed that fertilizer management is critical, and fertigation is very useful for no-till systems. Further work is being conducted to verify the viability of these systems in 2015 and facilitate successful on-farm implementation of this technology in the region.