Comparison Blackberry Production Under High Tunnels and Field Conditions. High Tunnels

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1 Comparison Blackberry Production Under High Tunnels and Field Conditions Dr. Elena Garcia Professor Dept. of Horticulture University of Arkansas High Tunnels What are high tunnels? High tunnels are passively heated and ventilated, plastic-covered structures that provide an intermediate level of environmental protection and control compared to open field conditions and heated greenhouses. (Source: Hightunnels.org) 1

2 Advantages of high tunnels relative to field production Season extension/off season production Reduced moisture on foliage from rainfall and dew Lower disease potential Increased growth rates and production Increased heat unit accumulation and retention More even light distribution Reduced plant stress Exclude insect pests and some animals Plant health and food safety Controlled water application Higher quality products Potential Total Crop Harvest Season Growing Season Traditional Field Cropping Season Extended Season with High Tunnels Harvest Seasons Total Cropping Season Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Tunnels may extend the summer harvest season from 4-6 weeks during summer to weeks during the year 2

3 Potential for Other Fruit Crops in Tunnels Figs Kiwi Cherries and plums Peaches and Nectarines Grapes Gratitude Tunnel Gratitude Field Primocane-Fruiting: A Quick Review. Blackberries are a perennial plant with biennial canes Primocanes are the first-year canes that usually are vegetative only Floricanes are the second-year canes and these flower, fruit and die Primocane fruiting indicates that fruit is borne on firstyear canes 3

4 Potential Value of Primocane Blackberries 1) Later-season (fall) fruiting period 2) Potential to schedule production based on primocane management 3) Potential of two crops on the same plant in the same year (floricane followed by primocane) 4) Pruning cost reductions by mowing of canes (primocane crop only) 5) Avoidance of winter injury Problems with Primocane Fruiting Blackberries Berry production season is short: 4-6 weeks High late summer temperatures (>30 C) limit flower formation and fruit set Early fall freezes limit fruiting of primocane cultivars 4

5 Double Cropping System for Organic Blackberries and Raspberries in High Tunnels for Season Extension Curt R. Rom M. Elena Garcia Donn T. Johnson Heather Friedrich Jason McAfee Research Objectives Develop production systems in order to (3 studies): I. Advance spring floricane production II. III. (Study 1) Extend autumn primocane harvest season of blackberries and raspberries (Study 2) Evaluate double cropping (fall and spring) potential of primocane-fruiting blackberry and raspberry. (Study 3) 5

6 Study 3. Potential for double cropping primocane genotypes Blackberry Cultivars: Prime Jim, Prime Jan, APF 46 Raspberry Cultivars: Autumn Bliss, Caroline, Dinkum A) Extended fall production on primocanes (harvest Sept-Dec), plus B) Advanced spring production on floricanes (harvest May-June) Methods Berries planted spring 2006 in-row spacing of 0.25 m & row spacing of 2m plot size 6x11m Covered w/ HT in fall 2006 Study ended November, years of cropping Bumble bees (Bombus sp.) hives were placed in each tunnel for early spring pollination 6

7 Key Events 2006 Poor raspberry establishment in 2006 (very hot and dry summer, even with irrigation) 75% of Dinkum had to be replanted Blackberries had a good survival rate 2007 Easter Freeze ; record low temps 7-9 Apr, 2007 Lost floricane crop Significant primocane damage 2008 Early severe autumn freeze ended all studies 24-Oct 2009 Excessive rainfall in May-June affected spring crop, and Sept- Oct affected autumn crop in the field. Study Ended Nov

8 HT Environments HT reduce total PAR ~17-20% In the spring season, HT increases Growing Degree Hour (GDH) accumulation by about 50-60GDH Advanced phenology approx. 2-3 wks Frost Protection Required: Spring 2008, required 3 nights of frost protection Spring 2009, required 2 nights of frost protection In the autumn season, HT prevented frost and continued fall fruiting for 3 4 wks after field Field ended 1-Nov, 2007, 24-Oct, 2008, 28-Oct, 2008 HT ended 22-Nov, 2007, 24-Oct, 2008, 24-Nov, 2009 HT can supercool on some nights Requires frost cloths for both advancing the season and protecting crop HT Frost Protection 8

9 GDH 11/9/2017 Growing Degree Hours Accumulation Study 1 and 3 - Spring First Harvest 1175 GDH GDH First Bloom ~60 GDH 565 GDH High Tunnel Field Budbreak 0 2/12 2/22 3/3 3/13 3/23 4/2 4/12 4/22 5/2 5/12 5/22 6/1 6/ Date GDH calculated using the Utah Model (Black, et al., 2008) Results: Average Seasonal Yields, Average Seasonal Yield (lb/plot) Spring Autumn Cultivar Tunnel Field Tunnel Field Blackberries APF Prime Jan Prime Jim avg Raspberries Autumn Bliss Caroline Dinkum avg (Average of 2 spring and 4 autumn harvests) 9

10 Mean Yield per Harvest (g) Mean Berry Weight (g) 11/9/2017 Average Berry Size, , Spring and Autumn Harvests Blackberry Genotype Raspberry Tunnel Field (Planted spring Severe freeze in spring Mean of 3 replications with 3 cv subplots) Average Harvest Weight ( ) Spring Autum Avg Season of Harvest Tunnel Field (Planted spring Severe freeze in spring Mean of 3 replications with 3 cv subplots) 10

11 Summary of Average Harvests With fruit harvested 2-3x/week, there were only small differences in the average harvest comparing high tunnels to field plots Tunnels tended to produce more fruit per harvest than field plots (7-10% on average) At peak harvest, tunnels produced 50% more fruit per harvest Although marketable yields were slightly higher in the tunnels (2-5%), they were not significantly different Summary Autumn Primocane Production Yield of Blackberry and Raspberry tended to be greater in HT than CK (field) Raspberry response tended to be greater than blackberry No significant effect of HT on average harvest and fruit size for blackberry However, avg fruit size tended to be larger Variation due to seasonal effects More pronounced for raspberries Differences in yield were due to Slight larger fruit size Slight increase in berry number Extended harvest season in HT by 3 weeks 11

12 Harvest, marketable grade, and estimated marketable yield of three floricane fruiting blackberries, 2008 (Study 1). Cultivar Total Harvest (lb) Marketable Yield (lb) Tunnel Field Avg Tunnel Field Avg Arapaho Navaho Ouachita ns avg Mowing Study: Materials and Methods PF blackberry genotype APF-52 was used in this study. In 2008 there were three mowing treatments: 1) canes were mown on 15 May; 2) canes were mown on 15 May and 10 June; 3) canes were mown on 15 May, 10 June, and 2 July. 12

13 Canes were pruned when they reached approximately 75 cm in height Fruit was harvested three times per week when ripe fruit was present First and last date of harvest, total yield, and average berry weight were recorded Mowing: Materials and Methods Because of concerns about impacts of multiple mowings on growth, in 2009, these treatments were adjusted: One treatment was 1) not mown and The other two treatments were mown once, either on 2) 15 May or on 3) 10 June. 13

14 Treatment Date of first harvest Not mown 21 Aug a Mown 15 May 22 Aug a y 19 Aug a Mown 10 June 29 Sep b 14 Sep b Yield (lb/row-m) Not mown 0.61b Mown 15 May 3.81a 1.39a Mown 10 June 0.20b 0.57b Location (lb) Ambient 3.13a 0.81a Hightunnel 4.88a 2.61b Berry size (oz) Not mown 0.190b Mown 15 May 0.197a 0.201b Mown 10 June 0.155b 0.243a Conclusion Mowing canes to ground level later in the season produced delayed harvest as well as reduced yields Mowing on 15 May did not delay harvest, but it did increase yields High tunnels extended harvest in 2009 when the first frosts were light, but not in 2008 when the first frost was a freeze Berry size was acceptable in all treatments 14

15 Collecting Foliar Samples in HT The objective of this project was to begin progress toward the development of fertilizer recommendations for primocanefruiting blackberry. To this end we propose to: Determine the sampling date with the least variation of elemental concentrations in the leaves of primocane-fruiting blackberries in North Carolina and Arkansas. Methods Foliar samples were collected from Prime-Ark 45 from several locations in AR and N Carolina The foliar sampling protocol was similar to that used for FF blackberry Leaves were collected from the fifth node from the apical bud Ouachita, a floricane-fruiting cultivar for added for comparison (Hughes et al., 1979) 15

16 Results There appears to be a period of relative stability of nutrient concentration means between 11 July and 25 July sampling periods in 2011 These dates coincide with 10 to 20 percent primocane bloom For Fayetteville and Clarksville in 2012 the results are not conclusive. This may be due to the excessive heat experienced in late June The Tunnel Team C. Rom E. Garcia D. Johnson J. Popp J. McAfee H. Friedrich D. Dickey B. Lewis C. Vincent German Rodriguez 16

17 Acknowledgements 17