University of Minnesota Day-neutral Low Tunnel Strawberry Project

Transcription

1 University of Minnesota Day-neutral Low Tunnel Strawberry Project Steve Poppe, Horticulture Scientist Emily Hoover, Dept Head/Professor Andy Petran and Jack Tillman, Graduate Students Emily Tepe, Research Associate Esther Jordan, Communications Specialist

2 Background Strawberries are an important part of a healthy diet Short MN growing season Day-neutral cultivars available to extend strawberry harvest Use of organic production methods Funding provided by the North American Strawberry Growers Association (NASGA) and the MN Dept. of Ag, MN Specialty Crop Block Grant

3 Long Term Impacts: Extend the harvest season and increase yields Aim to enhance profits Increase supply of locally produced organic strawberries Fruit available during a non-traditional time

4 Why Low Tunnels instead of High Tunnels In high tunnels: Space not used efficiently due to strawberry plant stature Increased incidence of diseases and insects Wind and snow damage Temperature gradient high between inside and outside

5 Project Objectives Grow Albion day-neutral strawberry plants on a raised bed in an open field vs. in a low tunnel system Develop recommendations for nitrogen requirements Evaluate production, fruit quality, pest, weed and disease management throughout the season Educate and develop more strawberry growers in the upper Midwest region

6 2015 Summary: Morris Albion yield and berry weight Treatment Low Tunnel Fertility Rate Average Yield/Plant (lb) Average Yield/Acre (lb) Average Berry Weight (g) 0x 1 ab ab 11.4 ab 0.5x 0.75 c c 9.2 c 1x 0.82 bc bc 9.8 bc 1.5x 1.12 a a 11.9 a 1-0x 0.94 abc abc 10.5 abc No Low Tunnel 0x x x x x

7 2015 Summary: St. Paul Albion yield and berry weight Treatment Low Tunnel Fertility Rate Average Yield/Plant (lb) Average Yield/Acre (lb) Average Berry Weight (g) 0x x x x x No Low Tunnel 0x 0.55 b 9933 b x 0.79 ab ab x 0.61 ab ab x 0.61 ab ab x 0.85 a a 9.8

8 Harvest Strawberry flowers removed 3 times Removed strawberry runners 3 times during the growing season Typically, harvest begins around the 3 rd or 4 th week of July Picked fruit until mid October

9 A Noticeably Sweet Berry Brix is a measure of total soluble solids Albion has relatively high brix compared to other dayneutrals Our 2013 June-bearing variety trial had an average brix level of 7.7 Brix content more influenced by harvest date than fertility of tunnel presence (St Paul)

10 Brix Content, St Paul LT PL 0x x x x x x x x x x LT PL 0x x x x x x x x x x LT PL 0x x x x x x x x x x 10.92

11 Temperature and Humidity Temperature and humidity recorded in the low tunnel and non-low tunnel beds Data loggers suspended 12 inches above both beds

12 Temperature and Humidity Low tunnel Non-low tunnel Low tunnel Non-low tunnel Low Tunnel Non-low Tunnel Average temperature Average relative humidity Average due point 71.3 F 68.2 F 64.6 F 63.6 F 67.3 F 66.2 F 82.4% 74.1% 78.2% 70.7% 81.7% 56.1%

13 Expenses (labor not included) Variable costs Total low tunnel Treatment per 100' Fertilizer $70 $11.67 Pesticides $17 $2.78 Plants $125/1000 (w/o shipping) approx. 17,500 plants/acre $25.00 Irrigation - drip tape $13/acre $2.22 Mulch - Plastic (white on black) $112.00/9600 of row $ mil Clear Film Roll $176.00/1640 $11.00 Galvanized Steel Hoops placed every 5 (Quantity: 20) $3.98 $79.60 Straw (for walkways) $56.00 $9.33 Hoops for beginning and end of each row, anchor pipe, steel stakes to anchor hoops and elastic bungee Tractor Fuel (tillage, bed prep, plastic laying) approx. 1 gallon/hour approx. 20 hours per acre, $3.50/gallon $ lb. plastic qt. containers $0.05 approx. 1 lb per plant & 200 plants per 100' row $10.00 Total costs (variable + fixed) $213.54

14 Projected Profit Projected profit based on 2015 data Average total yield/plant lbs Estimated marketable yield/plant (15% loss) lbs Average marketable yield/100 row lbs Average selling price/pound X $5.00 Gross profit/100 row = $ hrs labor to pick 100 row x $9.50/hr - $95.00 Total costs (variable and fixed, from last slide) - $ Net profit/100 row = $ acre (660 x 66 ) rows* Net profit/acre $28, * 6 row spacing

15 Low Tunnel Construction and Planting Steps Materials needed: Bed shaper Mulch machine 4 foot wide, 1 mil white on black plastic mulch Drip tape irrigation Dormant day-neutral strawberry plants

16 Creating a Raised Bed

17 Creating a Raised Bed Once the bed is created, a 4 foot wide 1 mil white on black plastic mulch is placed on top of the bed The dry wheel puncher makes small holes in the plastic to act as a guide for proper plant spacing

18 Creating a Raised Bed

19 Row spacing was 14 inches between rows, and 12 inches between plants in a staggered row Use a 1 inch x 12 inch wooden plant stake to transplant Place the blunt end of the wood plant stake at the tip of the roots and insert the transplant into the ground Planting

20 Low Tunnel Support Use pipe to anchor plastic hoop at the beginning and end of each row

21 Installing hoops and anchor stakes

22 Installing Tunnel Plastic 1.5 mil clear film roll

23 Securing Plastic Hoop with Elastic Bungee

24 Fertilizer Injector At grower sites, fertilizer applied through Ez-Flo injector Applied AgGrand water soluble organic fertilizer through drip tape

25 Fertilizer Treatments Chilean Nitrate, organic fertilizer, Perforated centrifuge tubes planted in the soil next to each plant Fertilizer solutions were mixed for each treatment in another centrifuge tube One ounce of solution is poured into each perforated tube beside each plant using this funnel device

26 Spotted Wing Drosophila (SWD) Very few, if any, SWD were detected in our traps at the Morris or St. Paul sites in 2013, 2014, or Applied Oxidate (OMRI Approved) for control at 1 oz./1 gallon water on a weekly basis at the Morris site

27 Spotted Wing Drosophila Traps Clear plastic quart-size cup, with lid Drilled 3/16 holes around the cup Wire handle inserted into the sides Yellow sticky traps inside the lid Trap cups monitored weekly New bait each week Recipe for SWD trap bait: 12 fl oz water 4 T sugar 1 T active dry yeast 1 T apple cider vinegar 1-2 T whole wheat flour

28 Tarnished Plant Bug Damage occurs when the insects use their sucking mouthparts to drink the sugars out of developing fruit Results in distorted, cat-faced berries at maturity Pressure was noticeably higher in 2015 than in leading to a reduction in total and marketable yields Present in both low tunnel and non-low tunnel treatments, however the damage was more severe in the non-low tunnel in early season at St. Paul At both sites a variety of organic insecticides were applied on a weekly basis Insecticides used were Mycotrol, Purespray Green, Pyganic and Oxidate

29 Strawberry Leaf Spot Infection is a continuous process with older lesions producing spores to infect young leaves during each season Spores are carried to new leaves by rain splash causing the disease cycle to begin again More prevalent on the non-low tunnel plant leaves versus the low tunnel

30 Strawberry Leaf Spot Control Most organic fungicides and biocontrol agents are not highly effective against overall disease complex on strawberry Products containing sulfur or copper have little or no activity against most leaf spot diseases In order to apply sufficient copper to obtain control, the potential for plant injury is probably unacceptable Emphasis for controlling these diseases should be placed on selection and use of disease resistant cultivars New alternative disease control materials for strawberries. Messenger Oxidate Trilogy Trichodex Many of these products have great potential but under moderate to high disease pressure effectiveness is uncertain. Information taken from Organic Small Fruit Disease Management Guidelines- Ohio State University

31 Iron Chlorosis Issue Chlorosis in day-neutral cultivars due to high soil ph Yellow foliage indicates a lack of chlorophyll, the green pigment responsible for photosynthesis (sugar production) in plants This photo shows chlorosis on plants that are planted in a soil that measured 7.6 ph We have determined that these newer day-neutral cultivars will grow successfully in soils that have a ph of 7.3 or lower

32 Dubois Retractable Tunnel System Advantages No wind damage issues Faster/simpler to install as compared to our original system Less costly than original system Concerns Slight tearing of hoop plastic Our original 4 mil thick plastic provided better heat retention in October Sides tend to roll down

33 What We Learned Skillful management required throughout entire growing season Fertility: Need 2 nd year of data to make conclusions Multiple cultivars is better Faster installation of Dubois retractable tunnel system Insect and disease pressures posed significant challenges in 2015

34 this has the potential as a real production system Portola Special thanks to Nourse Farms for donating strawberry plants for the 2015 trial season

35 University of Minnesota West Central Research and Outreach Center Morris, MN Steve Poppe Horticulture Scientist Andy Petran Graduate Student Albion For more information visit our low tunnel blog