Alabama Cooperative Extension System, Alabama A&M and Auburn Universities

Bramble is a common term used to describe a diverse group of berries that includes raspberries, blackberries, and dewbenies.

The crown and root systems of brambles are peren­nial (they live for many years), while canes are bienni­al (they live for 2 years). In the spring, new canes emerge from buds on crowns or roots. During their first year these canes are termed primocanes (first­year canes) and usually do not flower. In the second year, following a dormant period, the canes flower and fruit and are termed floricanes (second-year canes). Primocanes grow in length rapidly following emer­gence and usually produce compound leaves. In con­trast, floricanes do not increase in length but produce a number of short, lateral branches with a few leaves and a terminal inflorescence (flower cluster).

Raspberries and blackberries are distinguished in the following way: when picked, the white receptacle (core) comes off with the blackberry fruit, and it remains attached to the raspbeny plant. Raspberries can be red, black, purple, or yellow. Some red and yel­low raspberries are considered everbearing because they produce fruit in the fall on primocanes and in the summer on floricanes. Blackberries can be either thorny or thornless.

Most raspberries are poorly adapted to the South because they lack heat and drought tolerance, while blackberries can withstand extreme heat and summer drought and are very well suited to the Alabama eli­mate. Bramble adaptation from best to worst for south­ern climates would be: blackberries, purple raspber­ries, black raspberries, and red raspberries. Raspbeny acreage in the South is limited to high, cool elevations or sites that are partially shaded from intense afternoon radiation.

Blackbenies are by far the most common bramble in the southeastern United States. Blackberries may be categorized into three types: (1) erect and semi-erect blackberry; (2) western trailing (that is, evergreen blackbeny and boysenberry); and (3) southern trailing blackbeny or dewbeny. Of these, the erect and semi­erect types are extensively cultivated, and the dewber­ry is cultivated on a limited scale. The western trailing types are not well adapted to the South, primarily because of their susceptibility to disease.

Ripe blackberries ready for haNest.

Most blackbeny cultivars (varieties) are climatically adapted throughout Alabama. Some Texas cultivars such as 'Rosborough' are vulnerable to winter injury when grown in areas where temperatures go as low as oo to 5°F. Semi-erect types such as 'Hull Thornless' should not be grown in areas where winter tempera­tures drop below zero. Disease pressures seriously lim­it the area of adaptation for many erect and semi-erect blackbeny cultivars.

Site Selection Selection of a suitable site for planting is the first

important step toward success in growing brambles. In addition to economic considerations such as nearness to markets, availability of labor, and accessibility, sev­eral topographical and biological factors require con-

Circular ANR-896

sideration. The two most important factors to consider in choosing a planting site for brambles are air drainage and water drainage. Brambles, like most fruit crops, are subject to damage from spring frosts at bloom time. Planting on sloping sites or level elevated areas will allow cold air to drain away from the black­berries on frosty nights. Low-lying sites or areas sur­rounded by trees that would impede air drainage should be avoided.

Brambles are damaged when water stands around their roots at any time of the year, and plantings on poorly drained soils are generally unproductive and shortlived. Poorly drained soils also encourage the development of such diseases as Phytophthora root rot. An elevated site providing air drainage usually also has good water drainage.

Another site characteristic worthy of consideration is the previous cropping history of the site and the nature of nearby crops. Blackberries should not be planted immediately following potatoes, tomatoes, peppers, or eggplants, since this increases the risk of infection with Verticillium wilt. Also, any site previ­ously planted to fruit crops with a history of crown gall should be avoided. When possible, new blackberry plantings should be separated from other cultivated or wild brambles by at least 350 feet to restrict disease infection.

Since blackberries do best in full sunlight, any trees bordering the planting site should be removed. Trees not only shade the planting but also compete for soil moisture, impede air drainage, and provide shelter for depredatory birds during fruit ripening. However, in large, open, windy areas, windbreaks may be essential to prevent cane breakage.

While the direction of the site slope is not a critical factor in selection, it can affect the time of bloom and fruiting. In most areas, blackberries on a southern slope will bloom and fruit slightly earlier than will those planted on a northern slope. The availability of water for irrigation near the planting is an important consideration because irrigation is necessary to obtain maximum production.

Blackberries grow and produce satisfactorily on a wide range of soil types, from sandy to heavy clay loams, provided that the drainage is good. Good soil characteristics for blackberry production are deep sandy loams that are moderately fertile, high in organ­ic matter, easily worked, and retentive of moisture but well drained. If the subsoil has a hardpan or the water table is high, the root system will be restricted and the plants will suffer during periods of drought. Blackberries are tolerant of a wide range of soil pH and grow satisfactorily within a pH range of 4.5 to 7 .5, but a soil pH of 6.0 to 6.5 is considered ideal.

Preplanting Operations

Preparing The Land Select the site and prepare for planting the year

before planting, if you can. This will allow time for proper soil preparation, elimination of perennial weeds, fertility adjustments, elimination of some soil insect problems, and installation of an irrigation sys­tem. Highly competitive perennial grasses such as bermudagrass should be eliminated, either by repeated tillage under dry conditions or by a combination of tillage and herbicide treatment when ample moisture has induced succulent weed growth. In the fall several weeks before a killing frost is the most effective time to kill perennial weeds with a systemic herbicide such as Roundup.

It is advisable to grow a clean-cultivated row crop on the site the year prior to planting. This helps to eradicate weeds and improve soil tilth. Planting direct­ly after turning under sod increases the risk of damage from white grubs and other soil insects. If perennial grasses exist on the site, they should be destroyed by herbicides or tillage prior to planting blackberries.

If the soil is low in organic matter, growing and turning under a well-fertilized green manure crop or 1 0 to 20 tons per acre of barnyard manure in the fall prior to spring planting is desirable. Lime, if needed, may be incorporated at this time.

The site for planting should be prepared as early in the spring as possible. The soil should be plowed deep and disked and harrowed until well pulverized. If a hardpan exists, subsoiling is recommended. During land preparation, fertilizer may be incorporated into the soil. The amount of fertilizer used should be based on need as determined by a soil test.

Cultivar Selection Proper cultivar (variety) selection is essential if suc­

cessful commercial production is to be achieved. Yield potential, susceptibility to disease, ripening season, ease of harvest, cultural practices required, and postharvest shelf life should all be considered in the selection process. Many possible choices are available.

Blackberries The cultivars listed here have generally given the

best response. A small trial planting is strongly advised to evaluate performance before planting any significant acreage.

'Rosborough' Erect canes, very large, soft, slightly acid fruit.

Berry size, flavor, and productiveness are superior to 'Brazos.' Moderately susceptible to rosette. A 1977 release of the Texas Agricultural Experiment Station.

Choosing the correct cultivar is critical for successful commercial production.

The most widely planted newer variety in Texas. Early season. Little performance information available for Alabama.

'Choctaw' Erect canes, medium size, firm fruit. Good flavor.

Early season, ripens about 12 days before 'Shawnee.' A 1989 release from the University of Arkansas.

'Cheyenne' Erect canes, large, firm fruit. Berries are slightly

acid and good quality. Very susceptible to rosette. A 1976 release from the University of Arkansas.

'Shawnee' Very erect canes, medium-large, firm fruit. Flavor

similar to 'Cheyenne.' Highly susceptible to rosette and resistant to orange rust. 'Shawnee' does not have a ripening peak as most erect cultivars do and it ripens over a longer period of time. A 1984 release from the University of Arkansas. Late season. Perhaps the best yielding cultivar under Alabama conditions.

'Gem' Trailing canes and large size fruit of excellent quali­

ty. Plants are vigorous and resistant to anthracnose and leafspot. A 1967 release from the University of Georgia.

'Navaho' Erect, thornless canes. Medium size fruit with high

sugar content and excellent flavor. Firm berry with

0

perhaps the best post-harvest shelf-life potential. Yields are about 60 to 75 percent of those of 'Shaw­nee.' Tolerant of rosette but susceptible to orange rust. A 1989 release from the University of Arkansas. Extended ripening season, beginning one week after 'Shawnee' and continuing 2 weeks later than the last 'Shawnee' harvest.

'Arapaho' Erect, thornless canes. Medium size fruit. Yields

are about 60 percent of those of 'Shawnee.' Fruit begins ripening with 'Shawnee' but has a concentrat­ed ripening season of about 3 weeks. Appears to be resistant to orange rust and rosette diseases. A 1993 release from the University of Arkansas.

'Hull' Semi-erect, thornless canes, medium-large fruit.

Very acid if picked before fruit are a fully ripe, dull black, but fully ripe fruit have an excellent flavor. Trellis support is required. Susceptibility to rosette is not known. Late season, perhaps 1 month after 'Shawnee.' A very long ripening season makes it espe­cially suitable as a garden cultivar or to extend the commercial harvest of blackberries into the summer months. 'Hull' was released by the USDA (1981) at Beltsville, Maryland.

'Chester' Thornless variety is the newest USDA semi-erect

(1985); it is about 7 to 10 days later in ripening than 'Hull.' Very acid if picked before fruit are a fully ripe, dull black, but fully ripe have an excellent flavor. Same fruit size as its sister seedling 'Hull.' Trellis support is required.

Additional thornless cultivars that appear worthy of trial include 'Loch Ness,' a semi-erect cultivar release from Scotland in 1988, and 'Waldo' release, from Oregon in 1988.

Purple Raspberries Purple raspberries are the result of crosses between

red and black raspberries. The fruit resemble the red parent more than the black. The flavor is not distinctly like either parent but is very good; however, this fruit is not as popular as the red or black, probably because it is less well known. Varieties to consider include:

'Brandywine' Promising and worthy of trial. It is a vigorous,

large-fruited raspberry. Berries are tart and a good quality and make excellent jams and jellies. 'Brandy­wine' is propagated by tip layering; trellising is recom­mended.

'Royalty' A 1993 release from the New York Agricultural

Experiment Station. It is similar to 'Brandywine' in that it is vigorous and has very large fruit that ripen late in the season. The fruit are sweeter than 'Brandywine' fruit and also make excellent jams and jellies. 'Royalty' has multiple insect resistance and immunity to the raspberry aphid, which carries mosaic virus. 'Royalty' suckers like the red raspberry and has rela­tively stout canes. It is recommended for trial.

Black Raspberries Because of low yields and poor environmental

adaptation, there are few commercial black raspberry plantings in the Deep South.

'Bristol' Fruit are medium to large, well-formed, glossy, and

very attractive; they are very flavorful and their quality is excellent. Ripens early in the season. A 1934 New York release.

'Jewel' 'Bristol' is one of its parents. Its fruit size is larger

than 'Bristol' fruit and it has more disease resistance than other black raspberry cultivars. A 1973 New York release.

'Logan' Ripens early and its berries are large and attractive.

'Allen' Fruit are large and attractive and the plants are pro­

ductive and vigorous. Harvest is fairly concentrated with this cultivar. A 1957 New York release.

'Black Hawk' A very hardy cultivar from Iowa (1955). Fruit are

large and firm and ripen very late.

'Haut' Recently released from the University of Maryland

(1989). It ripens early and over a longer period than other black raspberry cultivars. Berries are moderate in size and very sweet.

Red Raspberries Red raspberries are not well adapted to Alabama cli­

matic conditions. They may perform be.st in partial shade or afternoon shade. Keep the soil heavily mulched around the plants and keep them well watered during the summer.

'Southland' Of North Carolina origin (1968); developed in

cooperation with the USDA. It is adapted to the un­even winter temperatures of the upper South. It has

good vigor and is resistant to leaf spot, mildew, and anthracnose. The spring fruit crop ripens early, and the berries are firm, medium sized, bright red, cone­shaped, and slightly acid with good dessert quality. Overmature berries may tend to crumble. The fall crop begins in August and continues until frost.

'Heritage' Of New York origin (1969); the predominant ever­

bearing red raspberry in the central and eastern United States. It is outstanding for its heavy fall crop. Berries are medium sized, firm, of excellent quality, and attrac­tive. The spring crop is only moderate. The plants are vigorous, producing many upright, sturdy canes that hold up their fruit well.

'Dorman Red' Of Mississippi origin (1972); has trailing canes and

requires an appropriate trellis. Medium size, attractive fruit have poor flavor. This is the most heat tolerant of all red raspberry cultivars.

Obtaining Planting Stock Selecting cultivars. Following site selection, the

next most important decision a grower makes relates to the choice of cultivar and the source of planting stock. A wrong decision on these matters is irreversible and cannot be corrected without starting over.

There are many cultivars of blackberries and rasp­berries available from which to choose; however, gen­erally only a few are well adapted to any specific region.

Sources of planting stock. After determining the cultivars to be planted, a grower must next locate a source of planting material. This is a critical decision since many serious production problems are directly associated with the planting material used, and, once introduced, may be difficult or impossible to eliminate. An essential prerequisite to success in bramble produc­tion is to start with disease-free planting stock, since the length of life of the planting and the annual produc­tivity are directly related to the health of the plants.

To assure getting healthy, true-to-name plants, a rep­utable source must be used. Many nurseries offer plants bearing state certification. This certificate indi­cates that the plants have been grown from special healthy stock under regulated conditions designed to eliminate, as much as possible, disease and insect pests. Every effort should be made to obtain planting stock developed under such a program. Do not use plants from an old planting unless they are carefully inspected by a person knowledgeable about bramble disease and insect pests.

Nursery stock is available as transplants, suckers, tips, root cuttings, or tissue cultured plants. Transplants are larger and more vigorous than suckers. Nurseries

develop transplants by replanting suckers (red raspber­ries) or tips (black raspberries and blackberries) and allowing them to grow another year. Transplants usual­ly cost more than suckers. The extra cost charged for these year-old plants is usually not worthwhile for commercial growers.

Dormant suckers are the traditional blackberry or red raspberry transplant. Black raspberries rarely pro­duce suckers. Purple raspberry suckers are sometimes used but, like black raspberries, they are most com­monly propagated by rooting primocane tips; that is, by tip-layering during late summer and fall.

To be good quality transplants, red raspberry suck­ers should retain a portion of the parent -plant root, so they may have an inverted T or an L shape. Transplants with relatively large root systems are acceptable, but those with few or no roots and no part of the parent root are less likely to survive.

Succulent red raspberry suckers (primocanes) may be transplanted in early spring when suckers are 5 to 8 inches tall; however, care must be taken to provide adequate moisture and weed control.

Black and purple raspberries and some blackberry cultivars are propagated by "tip-layering." This is usu­ally done in late August by burying the tips of the cur­rent season's cane 2 to 4 inches in the soil. The buried tips develop roots and form new plants before dorman­cy the same year. Cut them from the original plant before digging. About 6 inches of old cane (called the "handle") is left attached to the rooted tip. Plants are shipped with these handles attached.

Root cuttings can be used either to produce red raspberry and some blackberry cultivar transplants or to directly establish plantations for fruit production. Roots of variable lengths and Yl6 to Yl6 inch in diameter should be placed at about a 3-inch depth in the soil with approximately 2 ounces of roots per hill or per 3 feet of hedgerow.

In vitro "tip cultured" or so-called "tissue cultured" red, purple, and black raspberry plants are available from certain nurseries. When derived from virus-free parent plants and rooted in sterile potting media, this

Table 1. Suggested Plant Spacing At Establishment.

Type of Bramble

Thorned blackberry (erect) root pieces Thorned blackberry (erect) rooted plants Thorned blackberry (trailing) Thornless blackberry (erect) rooted plants Thorned blackberry (semierect) Red, yellow raspberry Black raspberry Purple raspberry

Spacing in rows (feet)

2 3

6-10 3

6-8 2

2.5 3

*Commercial plantings generally require 12 foot row spacings.

kind of transplant should be free of most serious dis­eases, insects, and nematodes.

Caring for the planting stock. Planting should be done when planting stock is dormant. Generally, early spring is the most desirable time. It is often necessary to store temporarily planting stock received from a nursery since weather and other factors may delay planting. Plants and root cuttings can be held success­fully in storage at 34 o to 36°F for several months if drying is prevented.

When plants or root cuttings arrive, open the pack­age and check the condition of the planting stock. If dry, they should be moistened. Unless planting is to be done within a few days, the plants should be heeled-in in a trench deep enough to cover the roots or wrapped in plastic and placed in a refrigerator. Whichever method is used to store the plants, precautions must be taken to prevent drying.

Spacing Suggestions Four factors determine spacing in a bramble plant­

ing: (1) the size of the farm equipment; (2) the training system desired; (3) the growth habits of the cultivar; and (4) the cost of transplants. The size of the farm equipment will determine the row width. The training system, the growth habits, and the investment desired will determine the distance between plants in the row.

Two types of training systems are used: the hedge­row and linear systems. All systems can be used with red and yellow raspberries and blackberries. Black and purple raspberries are usually trained to the linear sys­tem.

Hedgerow. This is the most popular training system for red raspberries. Set the plants at about 2Yz to 3 feet apart in the row and 6 to 12 feet between rows. Sucker plants from underground stems will form a solid and continuous row in 1 or 2 years.

Linear. This system differs from the hedgerow in planting. Fruiting canes come from the crown of the original plant. For red raspberries, set plants at the same distance as in the hedgerow system.

Spacing between rows (feet)*

10-12 10-12 10-12 10-12 10-12

10 10 12

Plants per acre

2,178-1,815 1,452-1,210

435-362 1,452-1,210

726-453 2,178 1,452 1,210

Management systems

Hedgerow Hedgerow High trellis Hedgerow High trellis Low trellis Low trellis High trellis

Planting Blackberries are generally planted in the late winter

or spring of the year. Fall planting is possible, but, in areas of freezing winter temperatures, fall-set plants should be protected by a mulch to prevent heaving. While early spring planting is desirable, planting should not be done until the soil is dry enough to work. The planting row should be prepared with the same care as that used for a seedbed for planting vegetables.

Blackberries should be planted in rows spaced 10 to 12 feet apart. The distance between plants in the row depends on the type of blackberry being grown and the training system to be used. Generally, plants of erect, thorny cultivars are set 3 to 4 feet apart in the row and allowed to fill in for establishment of a solid hedgerow. If root cuttings are used for planting, they often are set 2 feet apart for more rapid row establishment. Most trailing and semi-erect cultivars, both thorny and thornless, are set 6 to 8 feet apart in the row, depending on the vigor of the cultivar, and trained to a hill system of culture.

Under certain conditions, the direction to run the plant row deserves consideration. Where slopes are involved, cross-slope planting is better for irrigation and erosion control. In areas of occasional strong winds, it is best where possible to orient rows in the direction of strong winds, since a cross-wind can result in considerable breakage of primocanes. In areas of high temperatures during harvest, the fruit on the west side of north-south rows may sunburn.

During the planting operation, it is very important to prevent the plants or root cuttings from drying. Plants should be held in the field prior to planting in wet burlap bags in shade and should be set as soon as dropped. Plant roots and root cuttings can be protected from drying during planting by coating with a layer of mud. Other important points in planting are to set at the proper depth, allow proper space for spreading the roots laterally, and to firm the soil well. In many cases, irrigation will need to be applied soon after setting to ensure proper soil moisture for root survival and devel­opment.

Planting may be done in a furrow or in individual holes. Plants should be set at about the same depth as they grew in the nursery. Root cuttings should be cov­ered 4 to 5 inches deep on sandy soils and 2 to 3 inches deep on heavier soil types. Generally, blackberries are planted on flat land, as raised beds tend to dry too rapidly.

Weed Control The first consideration following planting should be

to control weeds effectively. Blackberries may be shal­lowly cultivated during the first growing season, but care must be taken to prevent breaking the tender,

newly emerging primocanes. Herbicides are also avail­able which, when properly used, can be effective in weed control. Generally, blackberry plantings are clean-cultivated between the rows by shallow tilling or disking. As the planting ages, blackberry roots will invade the area between the rows, and cultivating too deeply will injure roots and induce unwanted sucker­ing between the rows. If sod is allowed to develop between rows, it should be mowed several times dur­ing the growing season. Whether clean cultivation or sod is used in the middles, the row area must be kept free of weeds by either physical or chemical means.

Fertilization During The First Year Any fertilizer needs for the initial growing season

should have been identified by soil tests and corrected during preplant land preparation. However, if the plants fail to initiate vigorous growth, additional nutri­ents can be applied in the spring. Use of nitrogen fertil­izer should be avoided later than July since this may result in subsequent winter injury. A typical first-year fertilization should be about 200 pounds per acre of a 10-10-10 fertilizer 1 month after planting.

Training And Pruning Blackberries

Erect Types Training. Cultivars of erect blackberries are self­

supporting and can be grown without a trellis system. However, in small, home garden plantings, some type of support will minimize cane breakage from wind, cultivation, and picking operations. In commercial operations, erect types are grown in hedgerows, where­in the sucker plants arising from roots fill in the entire row space. The base of the row should be kept to a width of about 1 V2 feet by removing suckers that arise beyond this limit. The best plant density for the hedgerow system is four to six vigorous canes per lin­eal foot of row.

Pruning. Both summer and winter pruning is prac­ticed with erect blackberries. During the summer, pri­mocanes are topped-by cutting or pinching out the shoot tip--when they reach 3 to 4 feet. This removes apical dominance and allows lateral branches, which produce fruiting wood, to develop. It also prevents long, arching cane growth, which is more likely to result in cane breakage. Since primocanes emerge at different times, summer topping must be done several times during the growing season. During the summer also, unwanted suckers should be removed.

Since blackberry canes are biennial, the fioricanes die soon after fruiting. Dead canes can be removed at any time from the end of harvest to the next spring. Since old dead canes may serve as a reservoir of inocu­lum of disease and insects pests, early removal and burning is desirable.

During the dormant season, pruning consists of shortening lat­erals, removing weak and insect­and disease-infested canes, and thinning canes in areas missed during the preceding summer. Maximum productivity and largest fruit size will be realized when lateral branches are pruned to lengths of 12 to 18 inches.

Trailing And Semi-Erect Types

Training. Trailing and semi­erect cultivars must be trained to some type of support system. The support may simply be a strong post or stake, 4 to 5 feet tall, to which the canes are tied, or one of several variations of a wire trellis system. Generally, a greater yield and ease of harvest is obtained from training to a wire trellis. The most common trellis is a two­wire, vertical system constructed by stretching wire between posts set 15 to 20 feet apart in the row. One wire is attached 3 '12 feet above the ground and the other 5 feet above the ground. Canes are tied to these wires, running in both directions from the plant, during the early spring.

Pruning. Trailing blackberries are not topped during the growing season as are erect types. Instead, the primocanes are allowed to grow on the ground along the row until after harvest and old canes are removed, or until early spring. In areas of cold winter tempera­tures, canes may be protected from cold injury by covering with soil or straw. In the spring, canes are uncovered and trained to the trellis system. Spring training should be done before bud break to avoid injury to newly emerging shoots.

Following harvest, old flori­canes should be cut off at ground level, removed, and burned. No other summer pruning operations

A. Primocanes are summer topped at a height of 3 to 4 feet. This operation is performed over several weeks because these first-year canes reach the proper height for topping at different times. B. Prima­cane several weeks after summer topping, show­ing the growth of lateral shoots from leaf axils.

I

F

A

-B

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Blackberry and black raspberry development and pruning cycle: A. Summer fruiting of floricanes and growth of primocanes. B. Primocanes prior to sum­mer topping after fruited floricanes have been removed. C. Primocanes after topping. D. Lateral branching of primocanes in response to topping. E. Dormant canes prior to winter pruning. F. Laterals pruned back during dor­mant season. (Copyright Prentice-Hall, 1990. Used by permission.)

Vertical two wire trellis for semi-erect thornless blackberry culture. Left, plant before pruning; right, same plant after pruning.

Tie six canes to trellis

Remove rest.

Remove last year's fruiting canes (shaded).

are required with trailing types, since they generally do not sucker as do erect types.

During the latter part of the dormant season, eight to ten vigorous canes should be selected, cut back to 6 to 8 feet in length, and tied to the trellis. All other canes are removed. Lateral branches on the fruiting canes should be pruned to 12 to 18 inches in length. If training and pruning is delayed until after bud break, care must be taken to prevent damage to the tender new shoots.

Training And Pruning Raspberries Growers must use care when choosing training and

pruning strategies, since these practices are generally the most time-consuming and expensive parts of an operation. Different types of trellis systems and prun­ing procedures have been developed for the different classes of raspberries.

Primocane Fruiting Red Raspberries. Primocane fruiting red raspberries tend to have top heavy canes that require support for efficient harvest and movement in the planting. The trellis system for primocane fruit-

Shorten laterals and canes on trellis.

Summer t

Harvest

ing red raspberries is usually temporary, since trellis removal is necessary for mowing during the dormant season if only the fall crop is desired. Steel or wooden posts may be placed in the row at 25- to 30-foot inter­vals. Some growers attach a 3-foot cross arm at 4 feet (forming aT trellis), while other growers do not use a cross arm. Twine is run down both sides of the row and attached to either the post or the cross arm at 4 feet of height at blossom time. This procedure may have to be repeated at 5 feet of height at harvest if the canes are unusually vigorous or the crop load is heavy. The twine is removed following harvest.

Floricane Fruiting Red Raspberries. Several per­manent trellis systems can be used for floricane fruit­ing red raspberries. Since the developing primocanes interfere with the fruiting floricanes, trellis systems should minimize the interference. A V -shaped trellis is often used. Wires are strung along posts placed at a 20° to 30° angle along the outer margins of the plant­ing row. Floricanes are tied to the wires, and prima­canes are allowed to grow into the middle. Another trellis system used is a permanent T trellis similar to

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A simple, two wire raspberry trellis.

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the temporary T trellis described on page 8. Occasion­ally, floricane fruiting red raspberries are grown on a single wire trellis.

Pruning during the growing season is limited to removal of the dying floricanes immediately after fruiting. Cut these canes at the ground and remove them from the planting and destroy them. Do not tip primocanes during the growing season. Dormant sea­son pruning consists of topping the floricanes at a height convenient for picking and trellising. Do not remove more than 25 percent of the canes or reduc­tions in yield will occur. Be sure to remove any winter­killed wood. Thin canes to three or four per square

Straight-line chain allowing wire tightening, removal, and replacement at pruning.

foot, selecting the most vigorous and healthy. Maintain row width at 18 inches.

Growers of ftoricane fruiting red raspberries in other regions of the United States are investigating annual mowing as a way of reducing pruning costs. Each year a portion of the planting is mowed to the ground in early spring, similar to primocane bearing red raspber­ries. Mowing has the advantage of reducing hand prun­ing and cane thinning. Disadvantages include reduced berry size, reduced fruit quality, and reduced yield for a given area of land (the mowed portion does not bear fruit).

Black And Purple Raspberries. Trellis systems for black and purple raspberries are similar to systems used for ftoricane fruiting red raspberries; T trellises are commonly used.

Pruning during the growing season consists of removing ftoricanes after harvest and tipping prima­canes. Black raspberry primocanes should be tipped at about 28 inches. At least 4 inches of tip should be removed from the cane. Purple raspberries should be tipped at about 30 to 32 inches, removing 4 inches of growth. Tipping results in stocky, self-supporting plants with a large amount of bearing wood on lateral shoots. The planting will have to be tipped several times since primocanes do not grow at the same rate. Tipping should be completed by harvest time. 'Royalty' purple raspberries do not require summer tipping, since growth is much like a red raspberry.

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A double T trellis to hold canes in a narrow hedgerow. Double wires on either side of upper cross arm hold canes without the need to tie individual canes.

Remove ftoricanes immediately after harvest by cut­ting close to the ground. Dormant season pruning con­sists of removing all but five to eight strong canes per crown. Remove any winter damaged wood. Head back laterals to eight to ten buds (8 to 10 inches).

Fertilization Of Established Plantings The type and amount of nutrient elements to apply

to a bramble planting should be determined by soil or foliar analyses. In this way, a grower can apply only those elements that are actually needed. In the absence of soil or foliar tests, plant growth is a good indication of nutrient requirements. The nutrient element most likely to be needed is nitrogen. Blackberries utilize nitrogen in producing vegetative growth, which is directly related to future productivity. In most areas nitrogen will need to be applied annually.

The initial fertilizer application should be made dur­ing land preparation prior to planting. This application should be sufficient for the first growing season. In the second and following seasons, a general recommenda­tion is to apply 50 to 100 pounds per acre of actual nitrogen. This should be applied broadcast into the row area in early spring before growth begins. If the rows are mulched, the amount of nitrogen should be increased by 50 to 100 percent for the first 3 years. If plants show excessive growth, the amount of nitrogen applied should be reduced accordingly.

Animal manures are very good sources of nitrogen and also add organic matter to the soil. A general rate for applying manures is 6 to 8 tons per acre of cow or horse manure and 2 to 3 tons per acre of poultry manure. Manures should be applied during late fall or winter when plants are dormant. Unless composted, animal manures may be a source of weed seeds.

If blackberry middles are clean cultivated, a winter cover crop is recommended. Cover crops planted in late summer between the blackberry rows will check erosion, help harden the blackberry canes for the win­ter competition for moisture and nutrients, and provide valuable organic matter to the soil when turned under in the spring. Also, legume crops are available which will add nitrogen to the soil. Some good cover crops for blackberries are cowpeas, oats, and rye. Care must be taken with aggressive crops such as vetch to prevent the seeds from getting into the blackberry row.

Irrigation Although blackberry species survive extended peri­

ods of drought in their native habitats, a shortage of soil moisture can seriously reduce yields and fruit size of cultivated plantings. Lack of sufficient moisture in the spring will affect fruit development, and insuffi­cient moisture at any time of the growing season may have a detrimental effect on the subsequent year's

crop. Irrigation may be especially important in obtain­ing good survival and growth of first-year plantings. Later yields are dependent on rapid establishment of well-filled hedge rows.

In general, blackberries require about 1 inch of water per week during the growing season. More may be required during fruit development in the spring and during hot, windy weather. When this amount is not supplied by rainfall, supplemental irrigation should be used. Any method of distributing irrigation water to the plants is satisfactory. Many growers use sprinkler irrigation, but recently trickle irrigation systems have become popular in blackberry culture.

Under hot dry conditions, operate drip irrigation systems for at least 8 to 10 hours each week. More fre­quent, even daily irrigation may be beneficial on very sandy sites and in mature plantings. Irrigation amounts and frequency should be adjusted throughout the grow­ing season to correspond to evaporation rates. Based on averages for evaporation rates across the South, plants are actually using 0.7 inches of water per week in May and September, 1.4 inches per week in June and August, and 2 inches per week in July. Soil mois­ture reserves must be regularly replenished by rainfall or irrigation or plants will become stressed and suffer losses in growth and production.

Pest Control Many of the pest problems on blackberries can be

prevented by starting with clean planting stock and the subsequent application of good sanitary measures. By eradicating all wild bramble plants in the area and iso­lating new plantings from old ones, many disease and insect problems can be prevented. Plants showing symptoms of virus, crown gall, orange rust, or red­necked cane borer should be pulled from the field and burned. Timely removal and burning of dead ftoricanes after harvest and the removal and burning of winter prunings will reduce populations of destructive pests.

The most common disease and insect pests of black­berry are listed in Table 2. Although there are many such pests that occasionally are damaging to blackber-

Table 2. Major Insect And Disease Pests.

Major Bramble Insects

Strawberry weevil Spider mites Japanese beetle Blackberry psyllid Tarnished plant bugs Rednecked cane borer Tree crickets Thrips Aphids Sap beetle Stink bug

M<Uor Bramble Diseases

Double blossom rosette Orange rust Anthracnose Septoria leaf spot Crown gall Botrytis fruit rot (gray mold) Cane blight Powdery Mildew Phytophthora root rot

ries, only a few are so consistently destructive that a regular control program is warranted.

Insects And Diseases There are a number of insect and disease pests of

brambles. As a general rule insects and mites do not present a major problem but may be serious in isolated situations. Diseases, however, seriously limit the pro­ductivity of brambles each year. The major pests are listed in Table 2 and the three most serious diseases (double blossom rosette, orange rust, and anthracnose) are discussed in detail below. Growers should refer to Circular ANR-478, "Small Fruits IPM," for insect, dis­ease, and weed control recommendations.

Double Blossom Rosette. Double blossom rosette is a serious fungus disease of many cultivars of erect and trailing blackberries, particularly in the humid southern United States. Rosette occurs on red and black raspberry but is seldom serious. Rosette-infected blossoms do not form berries, and noninfected parts of the same cane may produce poor quality fruit. This disease seriously reduces fruit quality and yield.

The symptoms of rosette disease are striking and may completely change the plant's appearance. Buds on new canes of erect and trailing blackberries are infected in early summer. Generally, no symptoms will develop until the following spring, although a few "witches brooms" may develop during warm spells in late fall. In the spring numerous leafy sprouts develop from infected buds. These shoots are generally smaller than normal and have pale-green foliage that later turns a bronze color. This proliferation of shoots is referred to as witches brooms. Several of these witches brooms may be formed on one cane. Unopened, infected flower buds are abnormally large and coarse and frequently somewhat redder. Sepals enlarge and occasionally change into leaves. Flower petals may become green and leaflike. As flower buds open, petals are usually pinkish in color, wrinkled, and twisted. Pistils are usually larger and longer than normal and occasionally become abnormally shaped. The fungus produces a whitish spore mass that can cover the sur­face of the infected pistils and stamens. Berries do not develop from infected blossoms; noninfected parts of the same cane often produce small, poor quality fruit. In some varieties the witches brooms symptoms may not be apparent; however, the fruit set in infected blos­soms is always impaired.

Young buds on vegetative canes are infected in early spring. The double blossom fungus grows between the bud scales and surrounds the embryonic tissues within the bud. As secondary buds develop beside an infected bud, they are also invaded. After the bud is colonized by the fungus, very little happens. Infected buds usually remain symptomless until the

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next spring, although a few infected buds are some­times forced out in an unusually warm late fall. The fungus overwinters in infected buds and, during the winter, continues to grow within the bud. Bud prolifer­ation is induced. When infected buds break dormancy in the spring, they develop a large number of short, abnormal, and off-colored shoots-the witches brooms effect. Infected flower buds usually produce abnormal blossoms, upon which the fungus produces its spores. These spores are carried by wind or insects to the newly formed vegetative buds, which are only suscep­tible to infection in early spring. The fungus infects these buds and overwinters in them to cause new symptoms the next spring, thus completing the disease cycle.

Keep the planting and surrounding area free from wild blackberries. These wild hosts can serve as a reservoir for the fungus.

Sanitation is beneficial. Remove and destroy old fruited canes after harvest. Infected blossom clusters should be handpicked and removed before they open. This practice may be beneficial in the backyard, but it is probably not practical in a commercial operation.

In some production systems where the growing sea­son is long, trailing blackberries are cut off at the ground after fruiting. In this way infected buds are removed. Since spores that cause infections are found only in flowers, subsequent new growth that year is clear of the rosette fungus. The practicality of this method is questionable; it will most certainly not work in more northern regions where sufficient new growth cannot be obtained during the current season.

Sanitation and in-bloom fungicide treatments appear to be the most effective means of control, and this will probably be necessary to produce blackberries where the disease is a severe problem.

The trailing variety 'Gem' and the old Texas variety 'Humble' are resistant to rosette.

Orange Rust. Orange rust is the most important of several rust diseases that attack brambles. All varieties of black and purple raspberries, erect blackberries, and most varieties of trailing blackberries are very suscep­tible. Red raspberries are not susceptible.

Unlike most other fungi that infect brambles, orange rust develops in a systemic, perennial fashion. It grows throughout the roots, crown, and shoots of infected plants and is perennial inside the below-ground parts. Once plants are infected with orange rust, they are infected for life. Orange rust is debilitating, but it does not normally kill. Infected plants are usually stunted and weakened; they produce little or no fruit.

Orange rust infected plants can be easily identified shortly after new growth appears in the early spring. Newly formed shoots are weak and spindly. The new

leaves on infected plants are stunted or misshapen and pale green to yellowish. The weak, unthrifty appear­ance of infested plants is a very important point to remember when you consider control. Within a few weeks of leafing out, the lower surface of infected leaves is covered with blister-like pustules. These waxy lesions soon take on the powdery, bright orange rust appearance that gives the disease its name. These rusted leaves wither and drop in late spring or early summer. Later in the season, the tips of young infected canes appear to outgrow the fungus. At this point, infected plants may appear normal and are often diffi­cult to identify. In reality, the plants are systemically infected, and in the following years infected canes will be bushy and spindly, and they will bear no fruit.

In mid-spring, the bright orange spores are spread by the wind from the pustules on infected leaves to healthy susceptible leaves. These spores germinate in the presence of water. They may penetrate the leaf directly or enter through a stomate. Once inside the leaf, the fungus sends out branching filaments that pro­duce food absorbing organs within the soft-walled cells of the inner leaf. After establishing itself in the leaves, the orange rust fungus grows through the canes, crown, and roots until the plant is systemically infected.

Always start a planting with disease free, rust free, nursery stock from a reputable nursery. Never make root cuttings from a planting where orange rust has been a problem. Before setting out new plants, remove and destroy all nearby wild brambles that can serve as a reservoir for the rust fungus.

The careful and timely removal of infected plants from the planting is probably the most important con­trol method currently available for orange rust. Inspect plantings in early spring just after the plants leaf out. At this time orange rust infected plants are easily iden­tified. Identify infected plants, dig them up-roots and all-and bum them. Rogue out and destroy plants with rust symptoms before the orange spores are produced. Once the spores are produced, they cause new infec­tions that may not show up until the following spring.

There are no fungicides recommended for control of orange rust. Strict sanitation and taking care to plant disease free plants are the only control.

Anthracnose. Anthracnose, sometimes called dieback, is a common foliage and cane disease of brambles. The disease is first noticeable in the spring as small, purplish spots on new shoots and as purple­bordered spots on leaves. As spots on canes enlarge, they become oval in shape and gradually tum gray. Badly infected canes dry out and crack, and the cane tips die back. Leaf spots become white with age, and affected tissue frequently drops out, leaving a shot-hole effect. The causal fungus also attacks fruit, resulting in small, dry, scabby berries. One of the most serious

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problems associated with anthracnose is the decline and death of fruiting canes just ahead of and during early harvest.

Anthracnose control on susceptible varieties is accomplished by a combination of cultural practices and chemical control. Before planting, destroy any wild brambles in the immediate area. In humid areas where anthracnose is likely to cause greatest damage, tolerant or resistant varieties should be used.

Plant at sites having good air movement, and space plants wide enough apart to permit good air circula­tion. For established plants, remove and bum all badly infested canes soon after harvest. Weed and grass growth in the row should be kept down for good air circulation around plants.

Chemical control of anthracnose on susceptible varieties involves three to four fungicide spray applica­tions, beginning in early spring when leaf buds have swelled or are just begining to open. Timing of the first application is very important in preventing later buildup of causal fungus. Make sure all plant parts are covered thoroughly with spray material.

Harvesting And Marketing Blackberries are a very perishable fruit and must be

harvested, packed, stored, and marketed with utmost care if they are to remain in good condition. The best index of maturity is the ease of separation of the fruit from the pedicel. Fruit color is a poor indicator since most blackberries color before they are fully ripe, and there is a tendency of most pickers to harvest fruit that is still underripe and sour.

Pick-your-own harvesting of blackberries is an enjoy­able family activity.

Blackberries ripen from May in the southeastern U.S. production regions to July in the Pacific Northwest. The fruiting period of individual cultivars ranges from 4 to 7 weeks at a given location.

Fruit should be picked as frequently as every sec­ond or third day. Berries left on the plants until over­ripe will become soft and moldy, and they may fall to the ground. The best time of day to pick is in the cool of morning, but berries should never be picked when wet with dew or rain, since wet berries mold very quickly.

Berries should be picked by gently lifting with thumb and fingers. Very few berries should be held in

Recently harvested blackberries ready for market.

the hand at one time. Harvested berries should be placed gently in the container in which they are to be marketed; transferring from container to container results in unnecessary bruising. Harvested fruit should be protected at all times from the sun, since exposure for even a short time will result in the fruit turning red and the flavor becoming bitter. Removing field heat by rapid cooling will greatly extend the shelf life of the fruit.

Fully ripe blackberries of all types are extremely perishable and should be used within a day of harvest. Less mature fruit may be stored for a few days if fruit is promptly cooled and handled carefully during har­vest and transport. Newly ripe blackberries may be held for 2 to 3 days at a temperature of 31 o to 32°F, with a relative humidity of 90 to 95 percent. After this period, fruit gradually loses black pigment and takes on a less attractive reddish tone.

Picking containers should be shallow to prevent mashed berries. It is important to minimize handling. It is generally best to pick directly into 12-pint flats or gallon containers that are market-ready. Ideally, the picking container should be strapped to the waist or hung about the neck of the picker to free both hands and eliminate time wasted in handling the container.

The pick-your-own concept of direct marketing has greatly stimulated interest in blackberry culture in many areas. Where adequate population density exists, this is an ideal method of marketing blackberries. Unless direct marketing or local marketing is to be used, potential growers should establish a marketing outlet prior to planting blackberries.

A partial crop of fruit may be expected the second summer after planting blackberries. By the third har­vest season, full production is reached. A properly managed blackberry planting should yield 6,000 to 8,000 pounds per acre, and even higher yields are pos­sible. Since the crowns and roots of blackberries are perennial, a well cared for planting should remain pro­ductive for many years. @

Acknowledgments The authors gratefully acknowledge the use of

materials from the following references in the prepara­tion of this publication.

Moore, J. N., and J. M. Skivin. 1990. Blackberry management. In Small Fruit Crop Management. Englewood Cliffs, N.J.: Prentice Hall.

Raspberries and Blackberries: Their Breeding, Diseases, and Growth. 1988. Ed. D. L. Jennings. Academic Press, $50.00. Order from: The Olde Pecan Bookstore, P.O. Drawer CC, College Station, TX 77841.

Compendium of Raspberry and Blackberry Diseases and Insects. 1991. Ed. M. A. Ellis et al. $25.00. APS Press, 3340 Pilot Knob Road, St. Paul, MN 55121.

Small Fruit Crop Management. 1990. Ed. G. J. Galletta and D. G. Himelrick. Englewood Cliffs, N.J.: Prentice Hall. Calll88-223-1360 East of Mississippi.

Small Fruit Pest Management and Culture. 1989. Ed. D. Horton et al. $15. (Make check payable to Cooperative Extension Service) Agricultural Business Office, Room 215 Conner Hall, University of Georgia, Athens, GA 30602.

Commercial Blackberry and Raspberry (Bramble) Production in Tennessee. 1988. PB 1302. Ed. A. D. Rutledge et al. Extension Mailing Room, Univ. of Tennessee, P.O. Box 1071, Knoxville, TN 37901-1071.

Growing Raspberries and Blackberries in Kentucky. 1989. H0-15. Ed. G. R. Brown et al. Department of Public Information, 131 Scovell Hall, University of Kentucky, Lexington, KY 40546-0064.

Commercial Bramble Culture. 1987. Bulletin 964. G. Krewer et al. 1987. Extension Publication Office. Hoke Smith Building, The University of Georgia, Athens, GA 30602.

Bramble Production Guide for South Carolina. 1985. Circular 595. G. A. King, Jr. 1985. Bulletin Room, P and S Building, Clemson, SC 29634-5609.

Blackberry Production in North Carolina. 1988. AG-401. Ed. E. B. Poling. $.50. Make checks payable: N.C. State University. Publications Office, Box 7603, NC State University, Raleigh, NC 27695-7603.

Growing Blackberries in Missouri. 1984. Bulletin 39. Ed. G. K. Ames. Extension Publications, 222 South 5th Street, University of Missouri, Columbia, M065211.

Growing Blackberries for Pleasure and Profit. 1987. Publication 1553. Ed. E. Pols, Jr. et al. Publications Office, Room 128 Knapp Hall, Louisiana State University, Baton Rouge, LA 70893.

Brambles: Production, Management, and Market­ing. 1988. Bulletin 783. R.S. Punt et al. $13.65. Make checks payable: Ohio Cooperative Extension Service, 2021 Coffey Road, Columbus, OH 43210-1004.

Raspberry Production Guide for Virginia. 1985. Publication 423-700. H.D. Stiles. Extension Division Distribution Center, 112 Landsdowne Street, Blacks­burg, VA 25060.

Growing Raspberries in Missouri. 1991. Bulletin No. 43. P. L. Byers. State Fruit Experiment Station of Southwest Missouri State University, Mountain Grove, MO 65711.

Bramble Production. 1994. P. C. Crandall. New York, N.Y.: Food Products Press.

Bramble Production Guide. 1989. M. Pritts and D. Handley. Northeast Regional Agricultural Engineering Service, 152 Riley-Robb Hall, Cooperative Extension, Ithaca, NY 14853.

> ~ ALABAMA,.. COOPERATIVE

Extens1on SYSTEM

CIRCULAR ANR·896

David G. Himelrick, Extension Horticulturist, Professor; Arlie A. Powell, Extension Horticulturist, Professor; and W. A. Dozier, Jr., Professor; all in Horticulture at Auburn University.

Use pesticides only according to the directions on the label. Follow all directions, precautions, and restrictions that are list· ed. Do not use pesticides on plants that are not listed on the label. ·

The pesticide rates in this publication are recommended only if they are registered with the Environmental Protection Agency and the Alabama Department of Agriculture and Industries. If a registration is changed or cancelled, the rate listed here is no longer recommended. Before you apply any pesticide, check with your county Extension agent for the latest infonnation.

Trade names are used only to give specific information. The Alabama Cooperative Extension System does not endorse or guar­antee any product and does not recommend one product instead of another that might be similar

For more information, call your county Extension office. Look in your telephone directory under your county's name to find the number.

Issued in furtherance of Cooperative Extension work in agriculture and home economics, Acts of May 8 and june 30,1914, and other related acts, in cooperation with the U.S. Department of Agriculture. The Alabama Cooperative Extension System (Alabama A&M University and Auburn University) offers educational programs, materials, and equal opportunity employment to all people without regard to race, color, national origin, religion, sex, age, veteran status, or disability.

UPS, 5M33, Rep. 9:96, ANR-896