University of Minnesota Low Tunnel Day-neutral

Strawberry Project

Preston Meyer, Student Intern

Steven R. Poppe, Horticulture Scientist

Emily Hoover, Head/Professor, Department of Horticulture Science

Introduction

● We are providing a fruit crop during a non-traditional time

● Increased production of strawberries would be good for MN strawberry farmers

● Can be grown organic

● New Day-Neutral cultivars available to extend strawberry season.

● Delicious

Why should people care about day-neutral strawberries in Minnesota?

Objective Determine the conditional differences between a Low Tunnel and a Non-Low Tunnel system. As well as the quality and weight of the yields.

Hoops are created as a means of protecting the plants from harsh climate conditions

Method: ● Create 6’’ raised soil bed to help with drainage and warming of soil.

● Cover with white on black plastic mulch to reflect sunlight and to prevent weeds. Drip irrigation for easy watering.

● Construct plastic hoops to keep out elements

Why Low Tunnels Instead of High Tunnels

In high tunnels:● Strawberries are low

growing, high tunnel space not needed

● In early research an increase incidence of diseases and insects

● Temperature gradient high between inside and outside

● Snow damage

Why Day-Neutral instead of June-bearing.

● Day-Neutral produce fruit during the same year as they are planted.

● Day-Neutral produce only some runners.

● Day-Neutral produce throughout growing season.

● June-bearers need at least a year to produce a significant yield

● June-bearers produce a lot of runners.

● June-bearers are classified into early, midseason and late varieties

2013-2014 Research Project● Compare day-neutral cultivars

grown on raised beds in low tunnel system vs. non low tunnel system

● Evaluate total fruit weight, fruit size, and fruit quality as well as pest, weed and disease incidences.

● Grow in 4 locations (2 UM sites, 2 grower fields)

● Evaluate 6 Day-neutral cultivars

● Plant new transplants each year

● White on black plastic mulch with drip irrigation

Flowers and Runners

● Flowers were removed continually several weeks after planting to delay fruit production

● This allows the plant to grow vegetation to support later fruit production

● Runners were removed 3 times during the entire growing season.

Yield

● After 5 harvests we have found that the Low Tunnel delivers almost twice the yield as compared to the non-low tunnel

● The Top Two Cultivars were Albion and Seascape

Diseases in Low Tunnel

● Powdery Mildew, caused by high humidity, was not found.

● Botrytis fruit rot- Not found in Low Tunnel or Non Low Tunnel

● Chlorosis- Majorly affected one cooperative site. Soil tests and water tests need to be taken.

Chlorosis found in cooperative trial

Insects in Low Tunnel ● Monitored for tarnished plant bug (TPB) and Spotted Wing Drosophila (SWD)

● 3 male SWD were detected

● Oxidate, an organic OMRI approved pesticide, which has been shown to control both TPB and SWD population, was sprayed.

Temperature Data for Low Tunnel

Temperature Data For Non-Low Tunnel

What do the graphs mean?

● What we have found is the low tunnel system on average is 10 degrees Fahrenheit warmer than the non-low tunnel system.

● This indicates that the low tunnel system could extend the growing season of the day-neutral strawberries into October, due to increased temperatures.

What did we learn or what can we do better

● Wrapping stoppers with duct tape held the stoppers in place.

● Drip irrigation could be placed in between strawberry plants, to prevent slipping.

● Creation of twine spine down the middle of the rods would help against bending.

Summary

During this project, we evaluated 6 cultivars and identified which ones were most successful.

We also discovered that within the first 5 harvests, yields were almost doubled.

The Low Tunnel system created, on average, a 10o degree increase compared to the Non-Low Tunnel.

This increase in temperature, as well as the use of day neutral strawberries could be used to extend strawberry season.