This project focuses on developing sustainable organic berry production systems using high tunnels and field production to extend harvest seasons and enhance yields. Key objectives include advancing early-season production of blackberries, extending fall harvests of various berry cultivars, and improving pest management. Results show significant yield increases of up to 206% through the use of high tunnels and innovative growing techniques.

1. This project aims to develop environmentally and economically sustainable organic
berry production systems combining high tunnel and field production to provide
season extension and increased yields.
Objectives:
1. Advance early-season production of floricane-fruiting blackberries
2. Extend the fall harvest season of primocane-fruiting blackberries and raspberries
3. Increase berry yield and quality through environment modification
4. Improve organic pest and disease management
Curt R. Rom1, Jason McAfee1, Luke Freeman1, Heather Friedrich1, Donn T. Johnson2, and M. Elena Garcia1
1Department of Horticulture, Center for Agricultural and Rural Sustainability, 316 Plant Sciences, University of Arkansas, Fayetteville, AR 72701
2Department of Entomology, 311 Agriculture Building, University of Arkansas, Fayetteville, AR 72701
Contact: Curt Rom, crom@uark.edu, University of Arkansas, 316 Plant Sciences Building, Fayetteville AR 72701
Introduction and Objectives
Materials and Methods
Results Discussion
This study was conducted at the Arkansas Agricultural
Research and Extension Center in Fayetteville, AR.
Study 1: Advancing Early-Season Production
• Blackberries: Natchez
• High tunnel (HT) and field (FD) plots
• Quonset-style HT (FarmTek), 20 x 87 ft, 6-mil
greenhouse plastic
• Tunnel-in-tunnel (TnT) built inside HT for increased
frost protection
• Pollination with purchased bumblebees (Biobest)
Study 1: Advancing Early-Season Production
• High tunnels and tunnels-in-tunnels advanced crop by 2-4 weeks
• Natchez yield increased by 39% in HT
• Must select earliest maturing cultivars to make it work most effectively
• Pest outbreaks inside HT: spider mites, aphids, white flies
• Only need the tunnels for 5 months/year
• An opportunity for movable tunnels
Treatment
Date of Full Bloom
Natchez Blackberry
2013 2014 AVG
Days
Advance
Field 1-May 6-May 4-May 0
High Tunnel 18-April 14-April 16-April 18 days
Tunnel-in-
tunnel
12-Apirl 8-April 10-April 24 days
Treatment
Date of Last Significant Harvest
Prime-Ark 45 Blackberry
2013 2014 AVG
Days
Extension
Field 15-Nov 1-Nov 8-Nov 0
High Tunnel 15-Nov 12-Nov 13-Nov 5
Tunnel-in-
tunnel
27-Nov 14-Nov 21-Nov 13
Study 1: Advancing Early-Season Production
0
10000
20000
30000
40000
50000
60000
Field High Tunnel
CumulativeYield(Lbs/acre)
Production System
Natchez Blackberry Yield
2012 2013 2014
39% Increase
10,031 lbs/acre
28,224 lbs/acre
0
5000
10000
15000
20000
25000
30000
5/28 6/2 6/7 6/12 6/17 6/22 6/27 7/2 7/7 7/12 7/17 7/22
CumulativeYield(grams/10ftplot)
Date
2014 Natchez Blackberry Cumulative Yield
FD HT
Study 2: Extending Fall Harvest Season
0
5000
10000
15000
20000
25000
30000
35000
40000
Field High Tunnel
CumulativeYield(Lbs/acre)
Production System
Prime-Ark® 45 Blackberry Yield
2012 2013 2014
206% Increase
0
1000
2000
3000
4000
5000
6000
7000
8/1 8/5 8/9 8/13 8/17 8/21 8/25 8/29 9/2 9/6 9/10 9/14 9/18 9/22 9/26 9/30 10/4 10/8 10/12
CumulativeYield(grams/10ftplot)
Date
2014 Prime-Ark® 45 Blackberry Cumulative Yield
FD Tot HT Tot
0
2000
4000
6000
8000
10000
12000
14000
CumulativeYield(gramsper10ftplot)
2013 Raspberry Yield
Autumn Bliss FD Autumn Bliss HT Josephine FD
Josephine HT Nantahala FD Nantahala HT
Figure 1. Natchez blackberry cumulative yield (lbs/acre*) for 2012, 2013, and 2014
in high tunnel and field production systems.
Figure 2. Natchez blackberry 2014 cumulative yield (grams/10 ft plot) over time in high tunnel (HT) and field (FD)
production systems.
Error bars represent standard error from the mean.*lbs/acre calculated at 8 ft row spacing
Figure 3. Prime-Ark® 45 blackberry cumulative yield (lbs/acre*) for 2012, 2013, and
2014 in high tunnel and field production systems.
*lbs/acre calculated at 8 ft row spacing
Figure 4. Prime-Ark® 45 blackberry 2014 cumulative yield (grams/10 ft plot) over time in high tunnel (HT) and field
(FD) production systems.
Figure 5. Raspberry 2013 cumulative yield (grams/10 ft plot) over time in high tunnel (HT) and field (FD)
production systems for cultivars ‘Autumn Bliss,’ ‘Josephine,’ and ‘Nantahala.’
*lbs/acre calculated at 8 ft row spacing
Error bars represent standard error from the mean.
Error bars represent standard error from the mean.
Table 1. Natchez blackberry date of full bloom in 2013 and 2014 in field, high tunnel, and
tunnel-in-tunnel systems.
Table 2. Prime-Ark® 45 blackberry blackberry date of last significant harvest in 2013 and
2014 in field, high tunnel, and tunnel-in-tunnel systems.
Study 2: Extending Fall Harvest Season
• Primocane Raspberries: Nantahala, Josephine, Autumn Bliss
• Primocane Blackberries: Prime-Ark® 45
• Primocanes managed for fall production only
• High tunnel (HT) and field (FD) plots
• Quonset-style HT (FarmTek), 20 x 188 ft, 6-mil greenhouse plastic
• Tunnel-in-tunnel (TnT) built inside HT for increased frost protection
• Insect screen (ProtekNet, Dubois Agrinovation) added to HT to exclude insect
pests
• Pollination with purchased bumblebees (Biobest, Inc.)
High Tunnel Production
• Increased daily heat accumulation
• Minimal heat conservation during a frost
• Tunnels-in-tunnels (TnT) provide increased daily heat accumulation over HT
• further advancing bloom and extending the season
• increased heat conservation during a frost; added 2-5oF above tunnels
• TnT can limit pollination
Study 2: Extending Fall Harvest Season
• High tunnels and tunnels-in-tunnels extended fall crop by 1-2 weeks
• Prime-Ark® 45 yield increased by 206% in HT
• Raspberry yield increased by 0-65% dependent on cultivar
• Autumn Bliss raspberry showed greatest yield potential inside HT
• Nantahala raspberry showed no yield response to HT
• Difficulty delaying flowering and fruiting of primocanes to capture season extension
• Tunnels may provide significant opportunity for organic pest management
• Temperature build-up with insect screen due to limited air circulation
High Tunnel Berry Research
Plots
‘Josephine’ Raspberries in High Tunnel
26 Sept 2013
Ethanol burners used for severe frost
protection
HighTunnelBerries.uark.edu