Producing Strawberries Throughout the Growing Season with a Small Environmental Footprint

May 2016

Steve Poppe, Horticulture Scientist

Day-neutral strawberries at the WCROCAvailability of locally grown strawberries is extremely limited in the Upper Midwest due to the short growing season and cultivars with short harvest windows. While there is an expressed interest in having greater access to locally grown strawberries, lack of knowledge regarding innovative production systems and new cultivars has limited growers from being able to fulfill this need in our region. 

Our current project continues to build on our last three years of research with organic production systems for day neutral strawberries to extend the season using plasticulture with and without low tunnels. Comparative field trials were established in 2015 on organic-certified land at the University of Minnesota West Central Research and Outreach Center (WCROC), Morris and the University of Minnesota St. Paul Campus. 

We examined nutrient requirements and pest management strategies for this system at these two sites. Low tunnel systems were also installed and planted at three grower cooperator sites in 2015.  Our project will develop recommendations for organic strawberry plasticulture with and without low tunnels to extend the harvest season and increase yield. 

Combining research with education will allow growers to implement this system, thereby increasing the supply of locally produced organic strawberries. Long-term outcomes aim to enhance profits and improve environmental sustainability for specialty crop growers.

A continuing objective from previous research was to determine if the use of a low tunnel system with day- neutral strawberries could provide adequate yields. Traditional June bearing strawberry varieties in Minnesota have a baseline yield of 5,500 pounds/A. As shown below in the summaries from Morris, yield of Albion in the low tunnel and non-low tunnel surpassed this baseline. 

Table 1: Summary of Yield 2015

Similar to our previous findings, day neutral production resulted in higher yields than the 5,500 lb/acre/year average observed with June bearing production, regardless of fertility practice or low tunnel use. Since the day neutrals in this production system are treated as annuals, growers can enjoy the added economic benefit of yield in the first year, rather than the typical no yield 'establishment year' common to June bearing systems. Similarly, labor and other management costs are saved by eliminating the need to overwinter the plants. Day neutrals managed this way can be incorporated into annual crop rotations, reducing the potential buildup of soil pathogens. 

For two years we have tracked our time and supplies with this research project.  Here are the variable costs associated with a 100’ row of low tunnel day-neutral strawberries.  

Table 3: Projected Profit

The chart below explains the projected profit based on our costs and 2015 yield data.

Table 3: Projected Profit

* = 6 ft row on center spacing