- Vegetables: cucurbits
- Production Systems: general crop production
The crimper/roller (C/R) system for killing rye was used to evaluate growing pumpkins organically and conventionally. Farmers throughout the Midwest desire new methods to keep pumpkins clean from soil. Clean pumpkins reduce the need for hand labor, which is expensive and becoming harder and harder to hire.
Fall seeded Wheeler rye produces very high plant biomass in the spring. Healthy vigorously growing rye will C/R better than stressed rye. Healthy rye will remain on the ground as a mulch and will not come back upright as long as it is C/R at the pollination stage. Conventional farmers can C/R earlier because they can treat the rolled rye with glyphosate to keep it from coming back up. The pollination growth stage of the rye at KBS usually occurs about the first week of June. This date can be late for soybean planting, but is very acceptable for pumpkin plantings.
Weed control in organic pumpkins is very difficult. We utilized several farmer advisory inputs to reduce weeds. We had good success growing pumpkins in 2009. Pumpkin yields from the treatments using rye and no-till were not as good as clean cultivation and the hand-hoed pumpkin treatment. We found that broadleaf weeds dominated when wheat straw was used in the zones where the pumpkins grew and grass weeds where we didn’t use straw. The rye mat did reduce soil on the pumpkins. Transplants matured earlier than planting by seed and had a higher percentage of orange pumpkins.
The C/R system worked very well in the conventional system. Our highest pumpkin yield resulted with clean tillage (no rye) or transplants with a zone burndown in 2009. Our cleanest pumpkins were seeded or transplanted directly into killed rye with no zones, however the yields were lower.
With an unseasonably cool summer in 2009, there was an advantage for growing pumpkins as transplants. Most farmers currently grow pumpkins from planting seeds.
The rye C/R system did provide excellent season-long weed control. Only two herbicide applications were used each year. We applied fungicide treatments every week from July 21 through September 15 in 2009. We never needed to use an insecticide treatment either year. This could be from the rye system, the cool season or our location.
In the Midwest and Northeast regions, pumpkin farmers use no-till planting following glyphosate burndown on cover crops like cereal rye (Secale cereal) and hairy vetch (Vicia villosa). This reduces herbicide applications (currently $22/A), decreases nitrogen fertilizer rates (currently about 140 lbs/A), limits the number of required tillage operations (about $16 to $29/A each) and provides mulch for pumpkins. The mulch also decreases pumpkin contact with the soil and mud, which reduces the incidence of soil-borne diseases and the need for fruit cleaning labor at harvest. Farmers and consumers—especially pick-your-own customers—have been satisfied with the new production system (Anonymous 2003), but the main challenge has remained the difficulty in managing the cover crops. In a previous SARE-funded project, Wyenandt et al. (2005) demonstrated the feasibility of no-till pumpkin production in Ohio and stressed the same limitations indicated above.
When rye is burned down too early, there is not enough full-season residue to accomplish the goals outlined above. When rye is too tall, burn-down herbicides are less effective and may require two applications for good control. In spring, hairy vetch is difficult to control with herbicides. The lack of complete control causes planter plug-ups and cover crop bunching in the field. This can result in competition from the hairy vetch and a poor crop stand. The C/R proposed for use in this study will improve the current no-till pumpkin production system by reducing the risk associated with poor cover crop management. Reduced reliance on burn-down herbicides and on environmental conditions favorable for their application could provide growers with more flexibility while enhancing their revenues.
- Determine appropriate cover crop management techniques to maximize biomass production.
Evaluate the C/R system for weed control, disease management and nitrogen availability.
Develop and implement an Extension and outreach program to disseminate results to Michigan and NCR growers.