Southern Highbush Blueberry Production in High Tunnels: Temperatures, Development, Yield, and Fruit Quality During the Establishment Years

Abstract

<jats:p>Growers interested in producing early, high-quality, southern highbush blueberries (<jats:italic>Vaccinium corymbosum</jats:italic> L.) in high tunnels face a lack of information regarding appropriate cultural methods. We sought to elucidate the optimal date to close high tunnels to hasten vegetative and reproductive growth of organic southern highbush blueberry cultivars Emerald and Jewel grown in Georgia. The three dates selected to close the high tunnels were 15 Dec., 2 Jan., and 16 Jan. High tunnels raised soil and daytime air temperatures during winter months, but the tunnels did not retain heat at night and did not provide freeze protection without the use of propane heaters. The high tunnel microclimate advanced both vegetative and reproductive growth compared with outdoor plants. Averaged over the 2-year study, the 15 Dec. tunnel closure advanced flower initiation by 38 days for ‘Emerald’ and 39 days for ‘Jewel’ compared with outdoor control plants. Synchronization of flowering of the two cultivars was poor in 2007 when ‘Emerald’ flowered much earlier than ‘Jewel’ and much better in 2008. In 2007, flower and fruit development of ‘Jewel’ were faster than that of ‘Emerald’ with Jewel going from the appearance of individual flowers to ripe fruit in 80 days as compared with 105 days for ‘Emerald’. Total yield was strongly correlated with fruit set (<jats:italic>r</jats:italic> = 0.94). ‘Emerald’ fruit contained higher concentrations of soluble solids and anthocyanins than ‘Jewel’ fruit, and anthocyanin concentrations increased throughout the harvest period. No fruit matured in 2008 as a result of freeze damage. The biggest obstacle for high tunnel production of southern highbush blueberries appears to be preventing freeze damage and assuring pollination. Cost-effective freeze protection and ways to promote good fruit set will be critical to successful production of early southern highbush blueberries in high tunnels.</jats:p>

High Tunnel and Field Production of Organic Heirloom Tomatoes: Yield, Fruit Quality, Disease, and Microclimate

“…Although the high tunnel system gives the grower additional control over the microclimate compared with the field, it is not always possible to maintain optimum daytime (25 to 30°C) or nighttime temperatures (%20°C) for crop growth. Increases in nighttime temperatures in the high tunnel compared with the field were modest as has been seen in other studies (Both et al, 2007;Giacomelli, 2009;Jett et al, 2004;Ogden and van Iersel, 2009;Waterer, 2003). On the coldest evenings, the difference of just a few degrees appeared to provide frost protection to the high tunnel transplants even when temperatures dropped below 0°C in the field.…”

“…This absorption was maximized in our system with the addition of black polypropylene landscape fabric over the soil. Cloud cover on cold evenings may also have reduced the rate of radiative cooling from the high tunnel (Ogden and van Iersel, 2009). The popular 'Cherokee Purple' tomato variety appears to be very susceptible to a number of fruit defects.…”

“…In addition, Florida strawberry yields were 54% greater and marketable fruit weight 69% greater in high tunnels compared with the field (Salame-Donoso et al, 2010). Flower and fruit production were accelerated for Southern highbush blueberry (Vaccinium corymbosum L.) in Georgia; however, the lack of nighttime freeze protection in the spring made the crop vulnerable to fruit abortion (Ogden and van Iersel, 2009). Minnesota production of high tunnel raspberries (Rubus fruticosus) benefitted from greater yields and extended seasons (Yao and Rosen, 2011) as well as increased fruit quality and decreased disease incidence for raspberry in Michigan (Hanson et al, 2011).…”

Performance of Southern Highbush Blueberry Cultivars Under High Tunnels in Florida

“…High tunnels are generally unheated, plastic-covered structures with passive ventilation (Lamont et al, 2002). Potential benefits of high tunnels for vegetable and small fruit production include freeze protection, high early yields, protection against some diseases and rain, and efficient fertilizer and water use (Lamont, 2005;Ogden and van Iersel, 2009;Strik, 2012). High tunnels may increase air and soil temperatures in areas of cold weather (Kadir et al, 2006;Reiss et al, 2004).…”

Planting Date Effect on Yield of Tomato, Eggplant, Pepper, Zinnia, and Snapdragon in High Tunnel in Mississippi

“…A blueberry production study in Georgia indicated HT closure advanced flower initiation by more than 30 days compared to field controls (Ogden and Iersel 2009). Research on strawberries in northern Utah showed HT production could advance the planting date by four weeks compared with outdoor production (Rowley et al 2010).…”