Raspberries and blackberries are the most commonly grown brambles, which also include minor fruits like dewberries and hybrids such as boysenberries. Bramble crops are high in value because they’re highly perishable and require significant investment to produce.
According to the North American Raspberry and Blackberry Growers Association, bramble fruits are high in Vitamin C and are good sources of folate and dietary fiber, yet are cholesterol-free and virtually fat-free. Raspberries and blackberries also contain a variety of substances that may help slow the aging process, boost immunity and protect against chronic disease, including the antioxidant anthocyanin and ellagic acid, a phenolic compound.
The raspberry is native to both Asia Minor and North America. The Romans left indicators that they had domesticated the raspberry as early as the fourth century, and by the 17th century berry bushes were abundant in British gardens. When European settlers came to America, they found Native Americans eating wild brambles, often drying them. The first commercial raspberry nursery in the United States started selling plants imported from Europe in 1771, and by 1867 over 40 varieties were known.
By 1880, approximately 2,000 acres were in cultivation; by 1919, production had risen to 54,000 acres, peaking at around 60,000 acres midcentury. Today, with improved varieties and horticultural practices, raspberry production is more intensive than in the past, and yields now average over 3 tons per acre nationwide. The leading red raspberry growing areas are Washington, Oregon and California, with production mostly for processing.
In the Northeast, freshly harvested raspberries are an important crop for pick-your-own farms, roadside stands and farmers’ markets. With the right mix of summer-fruiting and fall-fruiting varieties, local farms can offer fresh raspberries from July to October, until frost. With high-tunnel raspberry production, fresh berries may be available into November.
How they grow
Brambles are perennials, or at least their roots are. Each fall the roots produce buds that become shoots the next spring. The shoots, or canes, live for just two years. With summer-fruiting varieties of raspberries, the first-year canes, or primocanes, grow to full size, but don’t produce flowers or fruits. Instead, they winter-over and become floricanes the following year, when they bear fruit mid to late-summer, then die.
In fall-bearing raspberry varieties, first-year canes fruit late summer or fall. Fruit is borne on lateral branches that develop from the top of the primocanes after they reach a certain height. Typically, fall-bearing varieties are cut to the ground before the next spring, but the lower part of the cane will produce some fruit the following summer if left in place.
The fruits of raspberries and blackberries are not actually berries. They are really clusters of mini-fruits called drupelets, each containing one seed—they are technically aggregate fruits. In the middle of the aggregated drupelets is the receptacle, which stays on the plant when you pick a raspberry, but comes along with the fruit when you pick a blackberry.
Black raspberries, certain purple raspberries and thornless blackberries produce buds at the crown of the plant. New plants can be started by placing a tip of a young shoot underground in late summer.
Red raspberries are the hardiest of the brambles; black and purple raspberries and thornless blackberries are less winter-hardy, with reduced yields after winters where temperatures fall to 10 to 15 degrees below zero. With all brambles, it’s not just cold that can do damage, but also strong, drying winds or dramatic temperature fluctuations.
There are many varieties of brambles to choose from for hardiness needs as well as culinary and horticultural preferences. This list is adapted with permission from the work of Dr. Courtney Weber at the Department of Horticulture at Cornell University.
Early-Season Red Raspberries
Boyne has fruit that ripens early and is small to medium in size, somewhat dark and soft, with fair flavor and good freezing quality. It has excellent winter hardiness, but is susceptible to anthracnose. It is moderately resistant to late yellow rust and tolerant to Phytophthora root rot and crown gall, but is susceptible to raspberry fireblight. Boyne yields very well and is recommended for colder climates.
Killarney fruit ripens early, but after Prelude and Boyne. It is medium-sized, very bright red and may crumble. Flavor and freezing quality are good, but berries may soften in warm weather. It is moderately resistant to Phytophthora root rot, but is susceptible to mildew and anthracnose. Killarney is very hardy and is recommended for colder climates.
Prelude is the earliest summer fruiting cultivar available. The fruit is medium-sized, round and firm with good flavor. It is very resistant to Phytophthora root rot and has good cold hardiness. A moderate fall crop is large enough to warrant double-cropping. It is probably the best early-season cultivar available for the Northeast.
Midseason Red Raspberries
Canby fruit ripens midseason, is medium to large in size, firm and bright red with excellent flavor. It has moderate to poor hardiness, and buds may winterkill in cold climates. It is susceptible to Phytophthora root rot.
Claudia fruit is large and conical with good flavor and ripens mid to late-season; a late fall crop is common. It has acceptable cold hardiness for most areas. This is a new release that is relatively untried, but has performed well in central New York.
Emily produces large midseason fruit with good yield potential. It is susceptible to Phytophthora root rot and has suspect cold hardiness. This new release is relatively untried and has performed poorly in central New York.
Esta produces fruit mid to late-season that are large and conical with a mild, bland flavor. It is susceptible to Phytophthora root rot and lacks cold hardiness, but is resistant to leafhoppers. It needs trellising for easy picking. This is a new release that is relatively untried.
Nova fruit ripens in midseason and is medium-sized, bright red, firm and somewhat acidic in taste, and has a better-than- average shelf life. The plants are very hardy and appear to resist most common cane diseases, including rust. It will set a late fall crop.
Titan is slow to spread and is susceptible to crown gall and Phytophthora root rot, but is extremely productive. Fruits ripen mid to late-season and are extremely large and dull red, with mild flavor. Berries are difficult to pick unless fully ripe. With only fair hardiness, Titan is for moderate climates. It is resistant to the raspberry aphid vector of mosaic virus complex.
Late-Season Red Raspberries
Encore is one of the latest summer-fruiting raspberries available. It produces large, firm, slightly conical berries with very good, sweet flavor. It is moderately susceptible to Phytophthora root rot and has good cold hardiness.
K81-6 produces medium-tall canes with spines only at the base. The fruit is very large with good flavor that ripens late summer with average firmness. It is resistant to late yellow rust, but is susceptible to leaf curl virus and raspberry fire blight. Hardiness is judged adequate for most areas.
Anne produces large, conic, pale yellow fruit with very good flavor and texture mid to late-season. It produces tall upright canes, but does not sucker adequately for good stands. It is resistant to Phytophthora root rot.
Autumn Bliss is an early-ripening raspberry with large, highly flavored fruit. It ripens 10 to 14 days before Heritage, and much of the crop is produced within the first two weeks of harvest, an advantage in northern climates. It produces short canes with few spines, and the fruit is somewhat dark. It is susceptible to raspberry bushy dwarf virus.
Autumn Britten is early-ripening with large, firm, good-flavored fruit. It is taller than Autumn Bliss with better fruit quality, but slightly lower yields. It is a day or two later than Autumn Bliss.
Caroline is a large, good-flavored, conical fruit, and it produces tall upright canes. The short fruiting laterals can be challenging to pick, but yields are very good for the fall. It has moderate to good resistance to Phytophthora root rot.
Goldie and Kiwigold are nearly identical cultivars. They are amber sports of Heritage, similar in all characteristics except fruit color. Fruit blushes pink when fully ripe; Goldie blushes slightly more than Kiwigold.
Heritage is considered the standard for fall- bearing cultivars. It is very high-yielding, although the crop ripens relatively late. Fruit is medium-sized and has good color and flavor, firmness, and good freezing quality. It is resistant to most diseases. This cultivar is not recommended for regions with cool summers or a short growing season with frost before September 30.
Josephine’s fruit is large with average flavor and ripens midseason. It is resistant to Phytophthora root rot and leafhopper. This is a new release that is relatively untried.
Polana is an early-season cultivar that ripens two weeks before Heritage. The fruit is medium-sized with good flavor. Susceptible to verticillium wilt and Phytophthora root rot. It needs extra nitrogen to perform well.
Ruby is moderately vigorous with good productivity and ripens slightly ahead of Heritage. The fruit is large with a mild flavor. Ruby is moderately susceptible to Phytophthora root rot, and is suggested for fresh market or shipping in areas with longer growing seasons. It is susceptible to mosaic virus complex and resistant to late yellow rust and powdery mildew.
Bristol is vigorous and high-yielding, especially in a newly established planting. The fruit ripens early and is medium to large and firm, with excellent flavor. Bristol is hardy for a black raspberry, but should be tested to ensure adequate hardiness. It is susceptible to anthracnose and raspberry mosaic complex, but is tolerant to powdery mildew.
Jewel is vigorous, erect and productive for a black raspberry. This hardy cultivar appears to be more disease-resistant than others, including resistance to anthracnose. The fruit is firm, glossy and flavorful and ripens in midseason.
Mac Black is new and has not been tested much. It is a late-season black raspberry with medium-large berries. It is reported to have good cold hardiness, and could extend your black raspberry harvest by seven to 10 days.
Brandywine produces very tall canes with prominent thorns. Suckers grow only from the crown so the plant will not spread. It is susceptible to crown gall, but partially resistant to many other diseases. Fruits ripen later than most red cultivars and are large, dull reddish-purple and can be quite tart. Berries are best used for processing. This is a high-yielding cultivar.
Royalty is considered the best purple raspberry available. The canes are tall and vigorous, have thorns, and are extremely productive. Royalty is immune to the large raspberry aphid, which decreases the probability of mosaic virus infection, but is susceptible to crown gall. Fruits ripen late and are large and reddish-purple to dull purple when fully ripe. Berries tend to be soft, but sweet and flavorful. Excellent for processing. Hardiness is acceptable for northern growing areas.
For more information, the most comprehensive guide to growing raspberries in the Northeast is the newly revised “Raspberry and Blackberry Production Guide for the Northeast, Midwest and Eastern Canada” published by NRAES (Natural Resource, Agriculture and Engineering Service of Cooperative Extension), www.nraes.org This 157-page book includes many color photos and is available from small fruit extension specialists in most states for $37.
The author is vegetable and berry specialist with University of Vermont Extension based at the Brattleboro office.