Emmalea Ernest, Associate Scientist – Vegetable Crops; emmalea@udel.edu and Gordon Johnson, Extension Vegetable & Fruit Specialist; gcjohn@udel.edu
Highbush blueberries are long-lived and costly to establish, so choosing the right variety is an important decision with long term impact on the success and profitability of a planting. Many standard blueberry varieties that have been used in commercial production for decades should still be considered for use in new plantings. There are also several active blueberry breeding programs that have released new varieties in recent years, adding to the number of varieties available to growers.
The Mid-Atlantic Berry Guide contains descriptions of many of the available northern highbush blueberry varieties, including disease resistance information. At the University of Delaware research farm in Georgetown we established a highbush blueberry variety trial in 2011. We have also worked with Hail Bennett to evaluate a variety trial established at the same time at Bennett Orchards in Frankford, Delaware. Both trials include mostly newly released varieties that have not yet been well tested. Commentary on the varieties included in these trials is provided below.
The UD trial at Georgetown includes some southern highbush varieties, as well as northern highbush varieties. Southern highbush blueberry varieties were developed from crosses between northern highbush blueberry (Vaccinium corymbosum) and one or more of six related southern blueberry species including Darrow’s evergreen blueberry (V. darrowii) and rabbiteye blueberry (V. virgatum). Southern highbush varieties tend to be more heat tolerant and adaptable to a wider range of soil conditions. Some southern highbush varieties also have reduced chilling requirements, which means that they do not need as much cold during dormancy in order to induce flowering. This is necessary for production in some parts of the South with shorter periods of winter weather, but is a liability in the Mid-Atlantic, where plants may come out of dormancy to early, and be susceptible to freeze damage.
The southern highbush varieties in the Georgetown trial are, in general, very vigorous in their growth, compared to the northern highbush varieties. We have not observed freeze damage to vegetative growth in the southern highbush varieties, but some have had freeze damage to flower buds in some years.
When choosing blueberry varieties it is important to consider various traits in light of your goals for production:
Ripening Time: In Delaware, it is possible to have blueberries ripening from mid-June through August by planting varieties that ripen at different times. Consider when you want to have blueberries available when you choose varieties and how they overlap. For extended direct market sales, as many as eight varieties may be necessary to have continuous supplies. First harvest dates and peak harvest dates for the varieties from the Delaware trials are in Table 1.
Table 1. Maturity of Varieties in the Georgetown Variety Trial in 2015
| Variety | 1st Harvest | Peak Harvest |
| Reka | 11-Jun | 15-Jun |
| Star | 11-Jun | 15-Jun |
| Reville | 11-Jun | 15-Jun |
| Hannah’s Choice | 11-Jun | 15-Jun |
| Sweetheart | 11-Jun | 15-Jun |
| Toro | 15-Jun | 22-Jun |
| Draper | 15-Jun | 22-Jun |
| Bluecrop | 11-Jun | 22-Jun |
| Misty | 15-Jun | 22-Jun |
| Jubilee | 11-Jun | 22-Jun |
| Arlen | 11-Jun | 22-Jun |
| Lenoir | 15-Jun | 22-Jun |
| Bluegold | 15-Jun | 30-Jun |
| Darrow | 15-Jun | 30-Jun |
| Legacy | 15-Jun | 30-Jun |
| Bonus | 15-Jun | 30-Jun |
| Chandler | 22-Jun | 13-Jul |
| Liberty | 22-Jun | 13-Jul |
| Nelson* | 1-Jul | unknown |
| Aurora | 2-Jul | 28-Jul |
* Data from trial at Bennett Orchards.
Berry Size: Varieties that produce larger berries may be desirable for U-pick operations. Very small berries are not desirable for handpicking and take more labor to pick.
Concentration of Ripening: Some varieties have been developed to ripen most of the fruit at one time to accommodate machine harvest, others ripen fruit over several weeks. Varieties that ripen over a long period will give you a long harvest window out of one planting. However, even if hand-picking, a short harvest period can be helpful from a pest management standpoint because herbicide sprays may be applied in a more timely way in blocks that are past harvest, and the number of sprays for diseases and insects that must be planned around the harvest period is reduced. More concentrated ripening also reduces labor for picking.
Plant Vigor/Adaptability: Blueberries are adapted to an unusual set of environmental conditions (acidic soil with high organic matter that is well drained but moist). Some varieties are more adaptable to soils that do not meet these requirements (i.e. heavy clay soils, dryer conditions) than others. If it will be hard for you to replicate the ideal blueberry soil environment on your site, choose varieties noted for their broad adaptability.
Flavor: There is a good deal of variability in flavor between varieties. Some varieties have an “earthy” (dirt!) flavor that is unappetizing to most folks, others, sometimes described as “mild”, tend to have little flavor. If you are direct marketing, flavor will be a prime concern. If you are wholesaling, choose varieties on a combination of yield and flavor, poor flavor types reduce consumer demand.
Recommended Varieties from the Delaware Trials at Georgetown & Frankford
Reka – Early ripening, northern highbush variety with good yields in 2013-15, and early fruiting. Berry size is medium to small. Flavor is good but tart. Berries are dark blue, almost black.
Chandler – Northern highbush variety with moderate yield in 2013-15. Berry size is very large and flavor is good. Ripens later in the season and over a long period. Plant tends toward woody growth and does not produce many shoots from the ground. Upright habit and large berry size could be desirable for pick-your-own.
Aurora – Northern highbush variety with moderate yields in 2013-14 and high yield in 2015. Berry size is medium to large. Matures late with peak harvest at the end of July and picking into August.
Legacy – Northern/Southern highbush variety with good yields in 2013-15. Berry size is medium with good flavor. Late main season maturity. Legacy has southern highbush in its pedigree, but we have not seen freeze damage to flower buds.
Bluecrop – Northern highbush variety with moderate yields in 2013-15. This is a widely planted standard variety with good (familiar) blueberry flavor. Berries are medium in size. Easy and fast to prune. Early main season maturity.
Jubilee – Southern highbush variety with good yields in 2013-15. Berries are medium to small with good flavor. We have not noted significant freeze damage to this variety and it is very vigorous. The only drawback of this variety is the tendency toward small berry size. Early main season maturity.
Lenoir – Southern highbush variety with moderate yields in 2013 and 2014 and high yield in 2015. Berries are medium-sized with excellent flavor. This variety grows vigorously and we have not observed any freeze damage to flower buds in any of the years we have tested it. Main season maturity.
Nelson – Northern highbush variety that was planted only at the Frankford site. It was one of the best yielding varieties in that trial. Late mid-season maturity.
Recommended with Reservations
Bluegold – Northern highbush variety with good yields in 2013 and 2015 but low yield in 2014. Medium size berry with good flavor. Tends to produce many short shoots, and over-flower. Requires lots of detail pruning to maintain berry size and limit overproduction. Main season maturity.
Darrow – Northern highbush variety with good yields in 2013-15. Berry size is very large. Flavor is questionable. Late main season maturity.
Draper – Northern highbush variety with moderate yields in 2013-15. Berries are large with good flavor. Plants seem well adapted and vigorous but yields are not especially high. Early main season maturity.
Misty – Southern highbush variety with good yields in 2013-15. Berries are medium to small with good flavor. Berries have a lot of bloom and are light in color. We have seen some freeze damage on this variety each year, which is concerning, but it has not resulted in low yields. The plant grows very vigorously. Early main season maturity.
Not Recommended
Toro – Northern highbush variety with good yields in 2013 and 2014 but declining plant health and yields in 2015. Berry size is large. Plant tends toward woody growth like Chandler but maybe not as vigorous. Main season maturity.
Liberty – Northern highbush variety with low yields in 2013-15. Late maturing, similar to Aurora, but Aurora is later, higher yielding and more vigorous.
Bonus – Northern highbush variety with low yields in 2013-15. Berry size is very large. Plants have not established well at the Georgetown site. Early main season maturity.
Star – Southern highbush variety with low yields in 2013 and 2014 and moderate yields in 2015. Berries are large with excellent flavor. This is a very nice variety but we have observed freeze damage to flower buds each year which results in yield loss. Early maturing.
Arlen – Southern highbush variety with low yields in 2013-15. Berries are very large with good flavor. This variety has suffered significant yield loss from freeze damage to flower buds each year. Main season maturity.
There are several varieties that were added to the trial after 2011, and we do not yet have enough data on them to make recommendations. They are:
| Southern Highbush | Northern Highbush |
| New Hanover
Pamlico Beaufort Reville GeorgiaGem O’Neal |
Hannah’s Choice
Sweetheart Chanticleer
|