Advanced Row Cover Management for Annual Raised-bed Strawberry Production in Eastern Kansas

View the project final report

Commodities

• Fruits: berries (strawberries)

Practices

• Education and Training: demonstration, extension, farmer to farmer, on-farm/ranch research, technical assistance
• Farm Business Management: budgets/cost and returns
• Pest Management: row covers (for pests)
• Production Systems: general crop production

Locally-raised strawberries are a profitable crop for growers in the Midwest and U-pick operations benefit the communities in which they serve. In the Midwest, strawberries have historically been grown in perennial, (3-5 year) “matted-row” systems, but recently many producers have adopted annual, plasticulture systems that were developed in the Southeastern US. These systems contribute to environmental sustainability as they reduce the amount of water and herbicide used, and provide growers with economic and social sustainability as annual yields are higher and more consistent. The cold temperatures that we experience in the midwest combined with the annual nature of this system (plants set every fall and harvested in spring) present some significant challenges to growing plasticulture strawberries in the midwest. Cold winter temperatures can cause plant damage, particularly if the plants have not fully transitioned into winter dormancy. In the spring, frost protection is essential and this is often done with overhead irrigation. In Kansas, this practice is extraordinarily difficult as the volume of water required is typically not available and may not be accessible. Frost-protective row coverings are an excellent way to manage winter injury and spring frosts. They are applied in mid-late December and removed once temperatures warm up in the spring. Because of the need to balance fall plant growth with a successful transition to winter dormancy, it’s clear that we need to evaluate current methods for the timing of row cover applications in the Midwest. Additionally, the severity of spring frosts and potential winter injury leads many to believe that thicker row coverings will protect the crop better in this region. However, using thicker fabric may reduce yield due to lower light transmission. There is a critical need for advanced studies in this growing region that investigate proper cultural practices for plasticulture strawberry production.

We plan to evaluate two thicknesses of row covers in addition to two different timings of application and relate these factors to plant growth, as well as berry yield and quality. Typically, row covers are applied in Kansas when 25 days have occurred with night-time temperatures below 30 degrees F. We will compare this standard treatment with one that calls for row cover based on the occurrence of 35 nights of less than 30 degree F temperatures. This additional cooling period may encourage the plants to enter dormancy and therefore be less prone to winter cold damage. We will also make this comparison with standard 1 oz. and 1.2 oz row cover that is equivalent in all measures except for thickness (density). We will utilize a randomized complete block design with four replications so that data can be analyzed statistically. Plant growth and biomass will be recorded in addition to fruit yield and bloom counts to assess plant productivity. Four 100 foot rows were established within the 1.7 acre block of strawberries for the research trial in September 2011 and each bed contains 1 replicate for the RCBD (4 reps total). The four treatments (1 oz-25 days, 1 oz-35 days, 1.2 oz-25 days, 1.2oz-35 days) were randomly distributed across each bed as 25 foot plots, and fabric row covers will be applied in late December. In the spring, twenty plants (grown in a double-row at 12 inch in-row spacing) will be harvested from the central 10 feet of each plot to reduce inter-plot interference and fruit yield, marketability, and average fruit size will be assessed.

This research project will be well complemented with an outreach program that communicates our study through numerous venues. We will conduct a three-hour “twilight tour” of the research field during Spring 2012 and publicize this event through local and regional avenues of K-State Research and Extension. Douglas County and the surrounding Lawrence and Kansas City area is home to more than 100 small-acreage and organic farms and this event will generate a broader audience as our farm is accessible (less than 2 hour drive) to numerous growers from Kansas, Missouri, and Nebraska. Topics of discussion during the event will include strawberry production in addition to on-farm research and the details of this study. This event will be coordinated in collaboration with Douglas County Extension and Jennifer Smith as well as Dr. Cary Rivard will present.

We will also collaborate closely with K-State Research and Extension to generate a peer-reviewed extension publication in the format of a “research report”, a short video (6-8 minutes) outlining the project and results, and web content for K-State online resources as well as our business website (http://www.wohletzfarmfresh.com/).

This project will help to change behaviors by introducing growers and extension personnel to successful strawberry production and showing specific and practical management decisions based upon sound research. We will evaluate this project by identifying the adoption of strawberry production and the proper use of row covers in the Midwest as the result of our extension efforts. We will survey visitors of the “twilight tour” to find out about strawberry production and row cover management in the area and gather email addresses in order to re-survey those same people the following spring(s). We will also inquire about K-State Research and Extension materials generated from this study and identify their usage. We will also evaluate participants of the Great Plains Growers Conference to determine if our project will help them make decisions on their farms.