Proc. Fla. State Hort. Soc. 122:7–9. 2009.
Performance of Ten Cultivars of Rabbiteye Blueberries in North Florida
PETER C. ANDERSEN1*, JEFFREY G. WILLIAMSON2, E. PAUL MILLER2, AND PAUL M. LYRENE2 1University of Florida North Florida Research and Education Center, 155 Research Road, Quincy, FL 32351 2University of Florida, Department of Horticultural Sciences, Fifi eld Hall, Gainesville, FL 32611
ADDITIONAL INDEX WORDS. blueberry quality, fruit growth, Vaccinium virgatum, yield Ten cultivars of rabbiteye blueberries [Vaccinium virgatum Aiton (formerly Vaccinium ashei Reade)] were evaluated from 2006 to 2009 at the North Florida Research and Education in Quincy, FL. ‘Austin’, ‘Brightwell’, ‘Cimax’, ‘Pow- derblue’, and ‘Premier’ were planted in Spring 2003. ‘Alapaha’, ‘Ira’, ‘Ochlocknee’, ‘Savory’, and ‘Yadkin’ were planted in Spring 2005. Plant growth, yield estimates, berry weights, and berry soluble solids were determined. At an in-row spacing of 1.5 m, most cultivars formed a hedgerow after 3 to 4 years of growth. Berry weights averaged 1.0 to 1.6 g, and average soluble solids varied from 13 to 16 °Brix depending on cultivar and year. Details of 10 cultivars are listed.
Blueberry production in Florida has increased from a few hun- plants each of ‘Austin’, ‘Brightwell’, ‘Climax’, ‘Powderblue’, dred to more than 3000 acres during the last 20 years (Andersen and ‘Premier’ were planted at a spacing of 1.5 m and 3.05 m, et al., 2009). Most of the expansion in acreage has been a result of within and between rows, respectively. During Spring 2005, the production of low chill southern highbush cultivars (Vaccinium 15 plants each of ‘Alapaha’, ‘Ira’, ‘Ochlocknee’,‘Savory’, and darrowi L. x Vaccinium corymbosum L.) from the University ‘Yadkin’ were added to the planting. Soil type was an Orangeburg of Florida breeding program (Williamson and Lyrene, 2004). loamy fi ne sand (Typic Paleuduff, Silaceous). Prior to planting, Industry growth has been a function of new improved cultivars, a 1.5-m-wide in-row strip was rototilled and elemental sulfur high consumer demand, and an exceptional market window for was applied at 1 kg per 30.5 m of row. The 1.5-m in-row strip early ripening cultivars in April and early May. Rabbiteye blue- was supplied with pine bark mulch 6–10 cm thick at planting. berries (Vaccinium virgatum Aiton) have been grown in Florida Pine bark mulch was supplemented with partially composted for more than 50 years. The acreage is mainly in northern and pine straw during Dec. 2007. Drip irrigation was applied as north-central Florida; yields are low and erratic south of Ocala needed. Overhead irrigation was not provided for frost control. (Williamson and Lyrene, 2004). Rabbiteye blueberries are much Fertilization was with ammonium sulfate in February and June more sustainable than southern highbush blueberries. In northern at the rate of 52 g/plant (years 1–2) and 114 g/plant (years 3–6). Florida, rabbiteye blueberries often do not require many pesticide Bird netting was not provided. sprays, although after several years large plantings can sustain During 2009 plant height, plant width, and plant growth in- a reduction in yield due to damage by thrips and the blueberry dex were measured with a ruler. Plant width was only measured gall midge. Rabbiteye blueberries also do not generally require perpendicular to the row since the bushes had already formed a overhead irrigation for frost protection or bird netting for crows or hedgerow. Plant growth index was calculated as: (plant height + migrating birds such as the cedar waxwing. Rabbiteye blueberries plant width)/2. Yield was estimated on a scale of 0 (no crop) to are good candidates for organic culture. They bloom much later, 10 (full crop) from 2007 to 2009. Yield was not determined in and berry ripening coincides (June–July) with the production of 2006 because of herbivory by crows. In subsequent years, yield highbush blueberry cultivars from the North Carolina highbush was estimated from 2007 to 2009 before berry ripening. Berries blueberry industry. The success and profi tability of blueberry from each cultivar were harvested on 31 May 2006 (only for plantings are determined by the selection of a proper site and the cultivars that were planted in 2003), 6 June 2007, 11 June 2008, appropriate mix of cultivars, as well as marketing considerations. and11 June 2009. Berry weights were determined from 50 berry Most rabbiteye blueberries in Florida are U-Pic or are available samples, n=5. Soluble solids were determined for fi ve 3- to 5- from roadside stands, and are marketed locally, so that proximity berry samples of each replication of each cultivar with a PAL-1 to markets is an important criterion. digital refractometer.
Materials and Methods Results and Discussion
A planting of rabbiteye blueberries (Vaccinium virgatum Aiton) Yield ratings from 2007 to 2009 for the fi ve cultivars planted in was established in Spring 2003 at the University of Florida North 2003 are presented in Table 1. ‘Brightwell’ produced the highest Florida Research and Education Center in Quincy, FL. Thirty yield in 2007, followed by ‘Austin’ and ‘Climax’. Yield estimates tended to be higher in 2007 compared to 2008 and 2009. For all *Corresponding author; email: pcand@ufl .edu; phone: (850) 875-7122 3 years, ‘Brightwell’ produced the highest yield (8.5) and ‘Pre-
Proc. Fla. State Hort. Soc. 122: 2009. 7 Table 1. Yield rating and plant size of five rabbiteye blueberry cultivars 2). ‘Alapaha’, ‘Ochlocknee’ and ‘Savory’ produced the highest planted in 2003. yields in 2007 and 2009; however, yield in 2008 was relatively Yield ratingz Plant size (m) 2009 low for all cultivars. ‘Ochlocknee’ had the highest, and ‘Yadkin’ Growth had the lowest average yield rating of the cultivars planted in Cultivar 2007 2008 2009 Avg Ht Width indexy 2005. ‘Alapaha’, ‘Ira’, and ‘Ochlocknee’ were taller than ‘Savory’ Austin 8.2 bx 4.3 c 6.4 b 6.3 b 2.0 bc 2.0 b 2.0 b and ‘Yadkin’. Width varied from 1.3 to 1.4 m for all cultivars. Brightwell 8.9 a 7.8 a 8.7 a 8.5 a 2.0 b 1.8 c 1.9 b A hedgerow was achieved by 2008–09. Plant growth index was Climax 7.4 c 5.4 b 4.8 c 5.9 b 2.0 b 1.9 b 2.0 b highest for ‘Alapaha’ and ‘Ira’, intermediate for ‘Ochlocknee’ Powderblue 5.7 d 5.0 bc 4.1 cd 5.0 c 1.9 c 1.6 d 1.7 c and ‘Savory’, and lowest for ‘Yadkin’. Premier 5.7 d 2.7 d 3.3 d 4.0 d 2.2 a 2.1 a 2.2 a Berry weights of the rabbiteye blueberry cultivars planted in 2003 averaged 1.0 to 1.6 g (Table 3). Berries were generally zYield rating was on a scale of a 0 (no crop) to 10 (full crop). yGrowth index is calculated as: (plant height + plant width)/2. larger in 2006 and 2009, compared to 2007 or 2008. This was xMean separation in columns by Duncan’s multiple range test, 5% likely due to greater precipitation during late Spring 2006 and level. 2009 compared to 2007 and 2008. In 2006 (but not 2007 or 2008) berry weight of ‘Powderblue’ was less than the other cultivars. Table 2. Yield rating and plant size of five rabbiteye blueberry cultivars Average berry weights were higher for ‘Austin’, ‘Brightwell’, planted in 2005. and ‘Premier’ than ‘Climax’ and ‘Powderblue’. Soluble solids Yield ratingz Plant size (m) 2009 for the five cultivars varied considerably by year. There were no significant differences in soluble solids among the cultivars Growth in 2006 and 2007. In 2008 °Brix for all cultivars was very high Cultivar 2007 2008 2009 Avg Ht Width indexy x and higher for ‘Climax’ and ‘Powderblue’ than the other three Arapaho 5.7 a 3.1 b 8.3 b 5.7 ab 1.7 a 1.4 a 1.6 a cultivars. In 2009, °Brix was higher for ‘Austin’ and ‘Climax’ Ira 3.8 b 3.7 ab 8.3 b 5.1 b 1.8 a 1.4 a 1.6 a than ‘Brightwell’, ‘Powderblue’, and ‘Premier’. Ochlocknee 5.8 a 3.5 ab 9.2 a 6.2 a 1.6 a 1.3 b 1.4 b For the cultivars planted in 2005, berry measurements were Savory 5.2 a 3.7 ab 8.4 b 5.7 ab 1.4 c 1.4 a 1.4 b performed in 2007 for only ‘Alapaha’ and ‘Savory’, and in 2008 Yadkin 3.5 b 4.5 a 3.9 c 4.0 c 1.3 d 1.3 b 1.3 c and 2009 for all five cultivars (Table 4). In 2007, berries of zYield rating was on a scale of 0 (no crop) to 10 (full crop). ‘Savory’ were exceptionally large. In 2008 (a dry year), berry yGrowth index is calculated as: (plant height + plant width)/2. weights were low and soluble solids tended to be high, similar xMean separation in columns by Duncan’s multiple range test, 5% to what was noted above for the cultivars planted in 2003. In level. 2009, berry weight of ‘Ira’ and ‘Savory’ were about 2.0 g. Aver- age berry weights varied between 1.2 g (‘Ochlocknee’) and 1.6 mier’ produced the lowest yield (4.0). The average yield rating g (‘Savory’). Soluble solids was higher for 2008 than 2007 and for ‘Austin’ (6.3) was intermediate, followed by ‘Climax’ (5.9) 2009. Average °Brix varied between 13.0 and 16.0. and ‘Powderblue’ (5.0). Plant growth was such that a hedgerow A summary of each of the rabbiteye cultivars in this trial will was formed by 2007. There was not a great variation in plant follow. The production of blueberries is benefitted by cross- size among the five cultivars. Plant height varied from 1.9 to pollination, therefore at least two or three cultivars of similar 2.2 m, and plant width varied from 1.6 to 2.1 m. ‘Premier’ was chilling should be planted together. For additional information slightly taller and wider, and thus had the greatest growth index consult Krewer and NeSmith (2000) and Williamson and Lyrene of the five cultivars, and ‘Powderblue’ was slightly smaller than (2004). the other cultivars. ‘ALAPAHA’ was released from the University of Georgia in Yield ratings were lower for the cultivars planted in 2005 (Table 2001 and is patented. It has a chilling requirement of about 500
Table 3. Berry weights and soluble solids (°Brix) of five rabbiteye blueberry cultivars planted in 2003. Berry wt (g) Soluble solids (°Brix) Cultivar 2006 2007 2008 2009 Avg 2006 2007 2008 2009 Avg Austin 1.33az 1.07 ab 0.92 ab 1.77 b 1.28 a 14.3 a 13.8 a 17.2 b 14.6 b 15.3 a Brightwell 1.25 a 1.13 ab 0.89 ab 1.66 b 1.23 a 14.0 a 13.0 a 17.6 b 12.2 b 14.2 b Climax 1.20 a 0.92 b 0.62 c 1.49 c 1.08 b 16.5 a 13.3 a 18.9 ab 14.0 a 15.7 a Powderblue 1.01 b 0.95 ab 0.85 b 1.63 b 1.10 b 14.7 a 13.3 a 19.7 a 12.3 b 15.0 ab Premier 1.26 a 1.25 a 0.87 ab 1.77 a 1.29 a 14.6 a 11.8 a 17.0 b 11.9 b 14.0 b zMean separation in columns by Duncan’s multiple range test, 5% level.
Table 4. Berry weights and soluble solids (°Brix) of five rabbiteye blueberry cultivars planted in 2005. Berry wt (g) Soluble solids (°Brix) Cultivar 2007 2008 2009 Avg 2007 2008 2009 Avg Arapaho 1.28 bz 0.71 d 1.10 d 1.03 e 11.3 a 18.3 a 11.9 a 13.7 bc Ira --- 1.00 b 1.93 a 1.43 b --- 15.2 b 12.1 a 13.6 bc Ochlocknee --- 0.95 b 1.43 c 1.19 d --- 18.7 a 13.3 a 16.0 a Savory 1.88 a 1.14 a 1.89 a 1.63 a 11.2 a 15.0 b 11.4 a 12.6 a Yadkin --- 0.83 c 1.76 b 1.29 c --- 16.1 ab 13.4 a 14.5 ab zMean separation in columns by Duncan’s multiple range test, 5% level.
8 Proc. Fla. State Hort. Soc. 122: 2009. h. It blooms with ‘Austin’ and ‘Premier’, and just after ‘Climax’. h), and is adapted to Gainesville and further north in Florida. In ‘Alapaha’ bushes are vigorous and upright in growth habit. Berries southern Georgia it probably ranks second in popularity behind have a short fruit development period and ripen with ‘Climax’. ‘Brightwell’. Growth habit is upright and spreading. Berry ripening Berries are medium-large in size, have excellent firmness, good is the ‘Tifblue’ season from late June to mid-August. The name color and a dry scar. ‘Powderblue’ was probably derived from the abundance of wax ‘AUSTIN’ was released from the University of Georgia in 1996, rodlets on the berry surface resulting in a light bluish berry color. and has a chilling requirement of 450–500 h. Bloom and berry Berries are medium sized, have good firmness and flavor, and a ripening (early to mid June) are with or just after ‘Climax’. The dry stem scar. ‘Powderblue’ is amenable to mechanical harvesting. fruit are medium-large, with good color, stem scar and flavor. Potential pollenizers include ‘Brightwell’, ‘Ira’, ‘Ochlocknee’, ‘Austin’ is moderately vigorous and has an upright growth ‘Premier’, and ‘Tifblue’. habit. Fruit are slightly softer than ‘Climax’, but are amenable ‘PREMIER’ was released by North Carolina State University in to mechanical harvesting. ‘Brightwell’, ‘Climax’ and ‘Premier’ 1978. It has a chilling requirement of about 550 h. Plant growth are good pollenizers. habit is upright and vigorous. It is popular, in part, due to a short ‘BRIGHTWELL’ was released by the University of Georgia in fruit development period. Berry ripening is early from late May 1983. It has a chilling requirement of about 500 h. ‘Brightwell’ is to mid-June. Berries are medium-large, and have good flavor, perhaps the most consistent producer of all rabbiteye cultivars in color and a dry stem scar. Blueberry gall midge can be more north Florida and south Georgia. Plants are vigorous and upright. of a problem on ‘Premier’ than other cultivars. This cultivar is Berry size is medium, with good color, stem scar and flavor. marginally adapted to mechanical harvesting because it requires Berry ripening is mid to late June. It is reported to be partially frequent harvests to avoid soft fruit. Potential pollenizers include self-fertile. Companion pollenizers include ‘Alapaha’, ‘Austin’, ‘Austin’, ‘Alapaha’, ‘Brightwell’, and ‘Powderblue’. ‘Powderblue’, and Premier’. ‘SAVORY’ was released by the University of Florida in 2003, ‘CLIMAX’ was released by the University of Georgia in 1974, and is patented. It is a low chill cultivar (300 h). It blooms with and has a chilling requirement of 400–450 h. In many years ‘Climax’ and berry ripening is 1–2 weeks before ‘Climax’ (late flowering and berry growth can precede vegetative growth in May). ‘Savory’ is a large upright bush. To our knowledge, ‘Sa- the spring. It has sustained frost injury to flower buds and fruit vory’ produces the largest berries of any rabbiteye blueberry. It in some years. Plant growth of ‘Climax’ is upright and open. has high firmness and a small dry picking scar. ‘Austin’, ‘Bonita’, Berries are medium in size with good color, good flavor and and ‘Climax’ are suitable pollenizers. a small scar. Berry firmness is excellent and ‘Climax’ is very ‘YADKIN’ was released by North Carolina State University suitable for mechanical harvesting. Potential pollenizers include in 1997. It has a chilling requirement of 650–750 h and is only ‘Austin’ and ‘Premier’. adapted to the northern extreme of Florida. Plant vigor is moder- ‘IRA’ was released by North Carolina State University in 1997. ate. Berry ripening is late June–August. Fruit are average in size, It has a high chilling requirement (700–800 h) and, thus, only color, firmness and picking scar. There have been reports that adapted to the most northern parts of Florida. Berry ripening is mid ‘Yadkin’ has the propensity to overcrop with a poor return bloom June to late July. Berries are medium in size, with good firmness, the following year. Potential pollenizers include Brightwell’, ‘Ira’, picking scar and color. Ira is a good candidate for mechanical ‘Ochlocknee’, ‘Powderblue’, ‘Premier’, and ‘Tifblue’. harvesting. Good pollenizers are ‘Powderblue’ and ‘Tifblue’. ‘OCHLOCKNEE’ was released from the University of Georgia in Literature Cited 2002, and is patented. It has a chilling requirement of 650–750 h, and is only adapted to the northern part of Florida. Plant growth Andersen, P.C., J.G. Williamson, and T.E. Crocker. 2009. Sustainability is vigorous and upright. Berry ripening is late and similar to assessment of fruit crops for north and north central Florida. Univ. of ‘Tifblue’ (late June to mid-August). Berries are medium in size Florida EDIS Publ. HS 765.
Proc. Fla. State Hort. Soc. 122: 2009. 9