Grapes Berries

GARDENGrapes Berries

GARDEN&

for the

North Carolina Cooperative Extension ServiceNorth Carolina State University

ContentsContents

Variety Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2

Soil Testing and Planting . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

Fertilization, Irrigation, Cultivation, and Mulching . . . . . . . . . . .6

Training and Pruning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

Harvesting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13

Pest Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13

Grapes and berries are well suited to the home garden. A small

planting can produce an abundance of fruit to eat fresh, to

freeze, and to use in making juice, pies, and preserves. In North

Carolina, our soils and climate permit growing a wide range of small

fruit crops. The most popular small fruits are strawberries, grapes,

brambles (blackberries and raspberries), and blueberries (Table 1).

Although home-grown fruit does not require as much care as that

grown commercially, good horticultural and pest management practices

are important. This publication presents detailed suggestions for estab-

lishing and caring for each of the small fruits.

Table 1. Bearing Age, Average Yield, Plant Quantity, and Potential Lifespan

Fruit Bearing Average NumberAge Annual of Plants Life

Yield for Four Expectancy(lb/plant) People (years)

BlueberryHighbush 3 8 6 20-30Rabbiteye 3 12 4 20-30

BlackberryErect 2 4 6 5-12Semitrailing 2 20 2 5-20

RaspberryRed and black 2 2-4 6 5-10

GrapeBunch 3 15 4 15-20Muscadine 3 25-50 2 15-30

StrawberryEverbearing 1 1/3 50 2-3Springbearing 2 1/2 50 3-4

Variety SelectionVariety Selection

There are many varieties of each fruit,but it is best to select only those adapted tothe climactic conditions in your area. Thiswill ensure good fruit quality and help pre-vent serious insect and disease problems,which are more likely to occur when usingvarieties not adapted to an area. Start withdisease-free, certified plants from a reliablenursery. It is not a good practice to use yourown plants or your neighbor’s plants.

Generally, choosing two or three vari-eties with different ripening dates will extendthe harvest season for any fruit. Selecting anumber of varieties of a fruit may alsoimprove pollination, especially for somevarieties of muscadine grapes (female types)and rabbiteye blueberries. Experimental dataand experience show that cross pollinationis very beneficial with blueberries. Plantingalternate pairs of rows of any two varieties ofthe same species has proved satisfactory.

BLACKBERRIESBlackberries are of two types: semi-

trailing thornless and erect (Table 2).Semitrailing thornless blackberries havecanes that are not self-supporting; they mustbe tied to poles or trellises. The fruit ripensabout one month after that of the erect type.The semitrailing type should not be grown inareas where winter temperatures may dropbelow Oo F. Erect blackberries can tolerate

temperatures slightly below Oo F without significant injury to canes.

BLUEBERRIESThe highbush blueberry (Vaccinium

corymbosum) is the type grown commer-cially in eastern North Carolina (Table 3).Home gardeners in the coastal plain, upperpiedmont, and mountains can also grow itas long as they closely follow the plantinginstructions. The rabbiteye type (V. ashei) ismore widely adapted to different soil typesbut will not tolerate the cold climate of themountains. Being resistant to drought andheat, it bears heavier crops than the high-bush type; therefore, rabbiteye varieties arehighly recommended for home gardens inthe coastal plain and piedmont. Their fruitripens about one month after that of thehighbush type.

RASPBERRIESRed raspberries are better suited to the

mountains of western North Carolina. Blackraspberries, which can better tolerate theheat, are more suitable for the piedmontand coastal plain (Table 4).

GRAPESGrapes are not as particular to soils as

are other small fruit crops. In fact, fertilesoils stimulate excessive vine growth at the

expense of fruit quality. It is therefore advis-able to take soil samples and follow theresulting recommendations. Homeownersmay choose to grow the vinifera varieties(the old-world grape) and French hybrids(crosses of vinifera and American grapes)for winemaking. Examples of the latter arethe Cabernet Sauvignon, Chardonnay, andSeyval. Better known to the home grapegrower is the American bunch grape, which includes varieties such as Concord,Niagara, and Delaware. The varieties listedin Table 5 are classified by region ratherthan type of vine.

STRAWBERRIESChoosing a strawberry variety depends

on many variables: disease resistance andfruit size as well as taste and length of sea-son (Table 6). If you wish to plant in thecoastal plain, choose anthracnose-tolerantvarieties because plants raised in this areaare very prone to the disease. For the moun-tain areas, mid- and late-season varietiesthat are resistant to red stele are recom-mended because the longer, cooler springencourages this cool-season fungus. Day-neutral varieties, Tribute and Tristar, are worthy of trial in the mountains if you wish to grow the everbearing type ofstrawberries.

Table 2. Blackberries for North Carolina

Variety Season Area Hardiness Yield Remarks

Erect VarietiesShawnee Mid to late All Good Good Thorny canes; sweet, large fruitKiowa Early to mid All Good Good Thorny canes; sweet, very large fruitArapaho Very early All Good Fair Thornless canes; sweetNavaho Late All Good Good Thornless canes; sweet; stores wellCherokee Early All Good High Thorny canes; very sweetCheyenne Mid All Excellent Excellent Thorny canes; good producer; sweet

Semitrailing VarietiesDirkson thornless Early to mid All Moderate Good Requires trellis; semitart, large berryHull thornless Mid All Low Excellent Requires trellis; sweet, soft berry

Table 3. Blueberries for North Carolina

Variety Season Color Size Flavor Remarks

Highbush Varieties for the Coastal Plain and PiedmontBluechip Early to mid Light Very large Excellent Upright plantBlueray Mid Medium Large Good Vigorous, uprightCroatan Early Medium Medium Fair Vigorous, uprightJersey Late Light Medium Good Vigorous, upright

Highbush Varieties for the MountainsBerkeley Mid to late Light Very large Good Susceptible to canker Blueray Mid Light Large Very good Performs well in all areas;

tight clustersCollins Early to mid Light Large Good Susceptible to canker; no crackingPatriot Mid to late Light Very large Very good Difficult to pickJersey Late Light Medium Good Vigorous; productive

Rabbiteye Varieties for the Coastal Plain and PiedmontClimax Very early Medium Medium Very good Upright; concentric ripening

to largePowderblue Mid to late Very light Medium Good Long season; no crackingPremier Very early Light Large Very good Disease resistant; uprightTifblue Early to mid Light Medium Good Standard variety;

to large vigorous, productiveIra Early to mid Medium Medium Good Firm fruit; productiveYadkin Early to mid Medium Medium Very good Very good flavor

to large

Table 4. Raspberries for North Carolina

Variety Season Area Plant Fruit Remarks

Red VarietiesSouthland June and Mountains Erect Light red, Heat tolerant, two

mid August Upper piedmont good quality crops annuallyDormanred June All Trailing, Glossy red, Good processed

vigorous fair qualityHeritage June to August Mountains Erect Deep red, Excellent flavor

Upper piedmont good qualityTitan June to July Mountains Trailing Red, large Well drained soilsBlack VarietiesAllen June (early) Mountains Erect Large, firm All-around varietyBristol June Mountains Erect Large, good quality Susceptible to

anthracnose Cumberland June Mountains Erect Large, Firm berry, hardy

excellent quality

Table 5. Grapes for North Carolina

Variety Season Color Size Use Remarks

Piedmont and Western RegionCatawba Late Red Medium Fresh, juice, wine All-purpose grapeCabernet-Sauvignon Very late Black Small Wine Vinifera, good to excellentCarmine Late Black Medium Wine Red vinifera, excellentChambourcin Late Black Large Wine Red French hybridChardonnay Mid White Small Wine White vinifera, excellent;

requires best siteConcord Early to mid Black Medium Fresh, juice Not recommended in

piedmontDelaware Mid Red Small Fresh, juice, wine Good for wine or tableHimrod Very early White Small-medium Fresh Seedless, excellent qualityLakemont Mid White Small Fresh Seedless, neutral flavorMoored Early Red Medium-large Fresh Fruity, productiveNiagara Mid White Medium Fresh, juice Fruity, hardyReliance Mid Red Medium Fresh Seedless, excellentSeyval Late White Large Wine French hybrid, good qualitySteuben Mid Black Medium-large Fresh, juice, wine Heavy producer,

good qualitySunbelt Mid Black Large Fresh, juice Similar to Concord but better

in piedmontVanessa Mid Red Small-medium Fresh Seedless, good qualityVenus Mid Blue Medium-large Fresh Partially seedless, avoid

overcroppingCoastal Plain and Lower Piedmont RegionCarlos Early White Medium Juice, wine Piedmont, coastal plain; good

scarFry* Early to mid Bronze Very large Fresh Coastal plain; susceptible to

blossom rotHiggins* Very late Pink Very large Fresh Coastal plain; disease resistantNoble Mid Black Small Fresh, juice, wine Piedmont, coastal plainCowart Mid Black Medium Fresh, juice, Coastal plainTriumph Early to mid Bronze Large Fresh Coastal plainNesbitt Mid Black Very large Fresh, juice, wine Piedmont, coastal plain*Female vine needs perfect-flowered variety to pollinate, such as Carlos, Noble, Cowart, Triumph, or Nesbit.

Table 6. Strawberries for North Carolina

QualityVariety Area* Season Size Yield Fresh/Processing Remarks

Atlas CP, P Early to mid Large High Good/Poor Pale flesh, susceptibleto anthracnose

Apollo All Mid to late Large High Good/Good Needs pollination;anthracnose tolerant

Allstar P Mid Large High Good/Good Resistant to red stele Cardinal P, M Early to mid Large High Good/Good Susceptible to red stele Titan CP, P Early to mid Very large Medium Excellent /Very good Hollow center; suscepti-

ble to anthracnoseTennessee M Late Small Medium-high Fair/Fair Susceptible to red steleBeautyEarlibelle CP, P Early Medium Medium Very good/Excellent Firm berry; susceptible

to anthracnoseEarliglow P, M Very early Small Medium Excellent/Excellent Best quality; red stele

resistantSweet Charlie CP, P Early Large Medium-low Excellent/Fair Adapted to matted

row and hill cultureTribute P, M Everbearing Large Medium Good/Good to high Deep redTristar P, M Everbearing Medium-small Medium Excellent/Good Deep red*CP-coastal plain, P-piedmont, M-mountains.

It is best to test the soil four to sixmonths before planting to allow adequatetime to amend the soil based on test results.If the pH is too low, raise it to the level sug-gested by the soil test with dolomitic lime. If the pH is too high, it can be lowered byapplying wettable sulfur (90 percent). Onsandy soils, apply 1 pound per hundredsquare feet for each unit the soil pH is to be lowered. For heavier clay soils, apply 2pounds per hundred square feet to lower

the pH one unit. Test the soil again beforeplanting, and till it well.

Keep plant roots moist until planting byeither heeling them into the ground tem-porarily or by wrapping them in wet burlap.Do not leave the roots exposed to the dry-ing effects of sun and air. If strawberryplants arrive when the soil is too wet forplanting, they can be stored in the refrigera-tor until the soil can be worked.

Prepare a planting hole large enough

to allow the roots to spread out naturally.Except for strawberry plants, spread out theroots of grapes and berries in the plantinghole. Strawberry plants should be plantedwith the roots straight down. Do not prunethe roots except to remove damaged ones.Set most fruit plants at the same depth theywere planted in the nursery. The crown (the point where the stem and root merge)should be placed at these depths:

• Blueberries—same as in the nursery if mulched, 1 inch below ground level if not

• Blackberries and raspberries—dormant plants 1 inch below ground level; tissue culture plants at ground level

• Grapes—at or slightly below ground level

• Strawberries—at ground level.

After planting, tamp the soil firmly toremove air pockets around the roots. Waterall new plantings well immediately afterplanting.

Blueberries, blackberries, raspberries, and grapes are generallyplanted in rows. Raspberries grow best in cool climates on deep, sandy loam soils.The soil should be well drained to a depthof 3 feet. Wait one year before plantingraspberries in ground on which sod hasbeen grown.

Strawberries are best planted in mat-ted-row systems. For a matted-row bed, setthe plants 1 to 2 feet apart in the row. Spacethe rows 3 to 4 feet apart (Figure 1). A mat-ted row is encouraged to develop from therunner plants that grow from the motherplant. Wait one year before planting straw-berries in ground on which grass sod hasbeen grown. Set plants with the rootsstraight down (never bent) and with thecrown even with the top of the ground(Figure 2).

Soil Testing Planting&Soil Testing Planting

Figure 1. Matted-row system for planting strawberries. Spacing is 1 to 2 feet withinthe rows and 3 to 4 feet between the rows. Runners are allowed to set in all direc-tions. Cultivation helps to straighten the runners into rows and to limit row width.

42”

24”

Original Planting

Final Stand

Matted row18” wide

BLACKBERRIESMixed fertilizers are satisfactory for

blackberries. For best results, apply fertilizerwhen growth starts in early spring and againin summer just after harvest. Use a 10-10-10commercial mix at the rate of 5 pounds perhundred linear feet of row. For late-ripeningthornless blackberries, apply the fertilizermix no later than July to avoid forcing late-season growth that will be subject to winterinjury. For the first year or two, before theroot system of the plants develops fully,spread 3 or 4 ounces of fertilizer in a 12-inch radius around the base of each plant.

Blackberries require abundant mois-ture while the berries are growing andripening. If rainfall is not adequate, provideirrigation water equivalent to 1 inch of rain-fall per week. A minimum rate of drip irriga-tion for mature blackberry plants is 2 gal-lons of water per day while berries aredeveloping.

Mulching reduces watering frequency

and helps control weeds and grasses thatcompete for moisture and nutrients. Goodmulching materials include pine straw, woodchips, and seed-free grain mulches, such aswheat or rye.

Blackberry plantings should be cultivat-ed thoroughly and frequently or mulchedvery well to keep grass and other weedsfrom getting a start. Once started, weeds aredifficult to control. Begin cultivating in thespring as soon as the soil is workable.Cultivate as often as necessary to controlweeds. Avoid deep cultivation so that you donot cut the blackberry roots. Undesirablesuckering becomes much more severe,especially on the erect varieties, when rootsare damaged. Discontinue cultivation at leastone month before freezing weather normallybegins. Herbicides can be useful on estab-lished blackberry plantings; contact yourcounty Cooperative Extension agent for suggestions.

BLUEBERRIESDo not fertilize newly set plants until the

first leaflets have reached full size. Apply 1tablespoon of special azalea fertilizer orother fertilizer with a 10-10-10 formulationin a circle 1 foot in diameter around eachplant. Repeat at six-week intervals throughmid-August in the coastal plain and mid-Julyin the mountains. Increase the amountapplied each year until a total of 1 cup inthree applications is being made by the fifth year. Reduce fertilizer rates by 50 per-cent on rabbiteye bushes when they growtaller than 5 feet and vegetative growth isexcessive.

Cultivate carefully, as blueberries areshallow rooted. If mulching is maintained,hand pulling of a few weeds should be allthat is required.

Maintain a 4- to 6-inch mulch of pinebark, sawdust, wood chips, or pine straw ina 3-foot diameter, or band and renew yearlyas needed.

Fertilization, Irrigation, Cultivation, MulchingFertilization, Irrigation, Cultivation, Mulching&

Figure 2. Correct planting depth for strawberry plants.

Too shallow Correct Too deep

RASPBERRIESBefore planting, spade or till into the

bed 1 pound of 10-10-10 fertilizer per hun-dred square feet of soil. Cultivate by handand hoe between rows to a depth of 1 to 2inches to prevent suckers from taking hold.Mulch with lawn clippings, pine straw, orpine bark.

Fertilize just after new growth starts inthe spring (May) with a 10-10-10 commer-cial mix at a rate of 5 pounds per hundredfeet of row. Repeat in July with another 2 to3 pounds per hundred feet of row if vigor islow. In subsequent years, apply 8 poundsper hundred feet of row in March andrepeat in May. Spread the fertilizer uniformlyin a foot-wide band over the row, or side-dress with half the recommended amount offertilizer on each side of the row.

GRAPESProper fertilization is essential to high

yields and quality. Before planting vines,broadcast and work fertilizer and lime intothe soil as indicated by your soil test (usual-ly about 2 pounds of fertilizer and 5 poundsof dolomitic limestone per 100 square feet).

After setting the vines and just beforegrowth starts, apply 1/2 cup (1/4 pound) of10-10-10 fertilizer in a 20-inch circlearound each vine. Repeat monthly until July15th. In the second year, double the first-year amounts but follow the same timeschedule. For bearing vines, scatter 1 to 2pounds of 10-10-10 fertilizer per plant overthe area. Repeat with 1 pound per vine inmid-June.

For at least the first two years, keep anarea 1 to 2 feet in diameter around eachvine free of weeds by hoeing, hand cultiva-tion, or mulching. Black plastic is a satisfac-tory mulch material, but it does not add tothe humus content of the soil. Do not use acombination fertilizer and weed killer onlawn areas near grape vines; the weed killermay be absorbed by the grape roots andinjure the vine.

STRAWBERRIESBefore planting, follow the soil test rec-

ommendations. If no soil test is made,broadcast about 4 pounds of 8-8-8 fertilizerfor each hundred feet of row two weeksbefore planting. For each plant, applyapproximately 1 teaspoonful of materialcontaining 16 percent nitrogen (or its equiv-alent) each time. Fertilize each plant set inspring with 2 teaspoonfuls about a monthafter setting. Apply this 16 percent nitrogenat least 4 inches from the plant crown. Applynitrogen fertilizer again between August 15and September 15. Three pounds of a 16percent nitrogen material, 2 1/2 pounds of20 percent, or 1 1/2 pounds of a 33 percentmaterial are adequate for each hundred feetof row. Scatter the material over the top ofthe plants while they are dry and use abroom to brush it off the foliage.

Very sandy coastal soils usually needadditional nitrogen again in late January orearly February. The rate suggested is halfthat of the fall application. Measure andapply nitrogen carefully; too much will causerank top growth and soft berries that rot

easily. For old plantings, use the sameamounts and same timing as for new planti-ngs.

Strawberry plants are shallow rooted.Dry weather and drought seriously reducethe size and yield of berries and the numberof new runner plants. For this reason, ifdrought occurs during planting, harvest,renovation, or bud set (from August throughOctober), plan to irrigate.

If you used disease-free plants in a mat-ted row and if they are still healthy at theend of the picking season, keep the sameplants for the second year’s crop. Thin theplants to approximately 8 inches apart in all directions. Pull off runners as they form. Cultivate the row middles, keepingthem clean of grass, weeds, and new runner plants. Fertilize as recommended for first-year plants. For hill system plants,set new ones each year; use only large runner plants. Transplant new plants during November or March when the soil is moist.

Apply pine needles or grain straw inFebruary in the coastal plain and piedmontand in December in western North Carolina.Scatter lightly over plants and in the middlesbetween rows. Do not completely cover thefoliage but cover well enough to protect thecrowns. Use a light application on top of theplants at the higher elevations after theground has frozen. In the mountains andelsewhere where high winds are expected,use old wire mesh or other suitable materialto hold the mulch in place.

Training PruningTraining Pruning&BLACKBERRIES

Train semitrailing blackberries to trel-lises (Figure 3A). The erect blackberry vari-eties do not require support if the tops ofnew canes are pruned during the summer tokeep growth below 3 to 4 feet. Erect black-berries that are not topped may be trainedto a one-wire trellis (Figure 3B).

Construct the blackberry trellis bystretching a wire between posts set 20 feetapart in the row. For erect blackberries, useone wire attached to the post about 30 inch-es from the ground. For semitrailing black-berries, use two wires at heights of 3 feetand 5 feet from the ground.

Erect blackberries such as Cherokeeand Cheyenne require pruning out of theroot suckers that arise from the crown.During the growing season, it is desirable toallow root suckers to develop to about a 12-inch-wide row. Any growth beyond thisshould be eliminated.

When the new shoots of erect blackber-ries reach 30 to 36 inches tall, cut off thetips. This will force branching lower on thecanes and will cause the canes to thicken,making them better able to support a heavyfruit crop. During the winter, prune the lat-erals to 12 to 14 inches for convenient har-vesting and larger berries. In late winter,remove any remaining dead or weak wood.Leave healthy, vigorous canes spaced at sixcanes per linear foot (Figure 4).

As soon as the last fruit has beenpicked in summer, cut all the old canes andburn them. This is also a good time to tipprune and thin new shoots.

Semitrailing blackberries should betrained to the trellis described above with asoft string. Generally, only a small crop offruit is produced in the first season. Ifgrowth is poor during this first season, cutthe canes back to several inches in late win-

ter to force development of sturdier, morefruitful canes. In the second and succeedingyears, shoot growth is more vigorous andupright. Tie these new shoots to the trelliswhen they reach a length of 4 to 6 feet.Some growers prefer to wait until harvest isover and old canes have been removedbefore tying new shoots to the wires.Pruning the old canes is critical to the pre-vention of disease. After harvest, prune dam-aged or weak canes, leaving four to eightnew shoots. Tie these canes to the trellis in afan shape (do not bunch them). In thespring before growth starts, prune any laterals back to 12 inches to encourage larger fruit.

BLUEBERRIESHighbush blueberries should be cut

back severely (removing all fruit buds) afterplanting. In late winter remove all diseasedand damaged canes. During the second year,again remove all fruit buds. In the third yearyou may leave a few fruit buds. During thefourth and succeeding years, leave half ofthe fruit buds and prune out diseased anddamaged canes. To control height, cut backtall, vigorous shoots to force lower-levelbranching.

Rabbiteye blueberries should bepruned similar to the highbush varieties forthe first three years; however, taller andmore limber shoots should be cut back to

Figure 3. (A) Train trailing plants to a two-wire trellis. (B) Train erect blackberry plantsto a one-wire trellis.

5’

A

B

3’ 3’ 3’ 3’ 3’

5’

2’

3’

10’

4’

stimulate lower, thicker branching. Onmature bushes, cuts in late July to remove orshorten vigorous upright shoots will controlheight and increase yields the following year.

RASPBERRIESRed raspberries tend to sucker and

spread. Most of their fruit production isconcentrated in the top third of new shootgrowth, so it is not advisable to prune theminto a hedgerow as you would with black-berries. Instead, they should be trellised.

Train Dormanred to a vertical trelliswith a narrow wall of foliage. Space posts 20feet apart and attach wires at a 5-foot height(Figure 5). For the Heritage variety, use acrossbar or horizontal trellising system.Two-foot crossarms are attached to the postsat a height of about 4 feet, and two wires aresecured at the ends of the arms (Figure 6).The new canes will grow between and besupported by the wires with a minimum oftying. Remove first-season blooms to helpplants get established and increase vegetativegrowth. Do not attempt to produce a cropthe first season.

During late February, thin the canes to4 to 6 inches apart over the width of therow. Keep rows to an 18-inch width. Be sureto select healthy canes and remove weakerones. After the harvest in summer, removeall canes that fruited to allow better growthof new season shoots and to prevent disease.

Make cuts close to the ground. It is prefer-able to thin new shoots in mid-summer,leaving three or four canes per foot of row.For Dormanred, tie the new shoots looselyto the trellis.

Black raspberries do not need to betrellised at all. They are treated much thesame as erect blackberries. Summer pruneby pinching back in June when new shootsreach 18 to 24 inches. It is sometimes nec-essary to do this a number of times, as notall shoots will be tall enough for pinching onthe same date. Terminal (end) growth stopswhen shoots are pinched back, but the threeto five buds below the pinched area developvigorous lateral growth. This allows the

canes to become self-supporting.After harvest, remove canes that have

just fruited. In winter before growth starts,cut back side branches, leaving two to sixbuds (8 to 12 inches long) per cane.Remove very small canes (Figure 7).

GRAPESTo simplify installation and avoid dam-

age to young vines, build and set the trellissystem before the vines are planted. Usewood treated to resist decay or a durabletype of wood such as cedar or locust.Construct the trellis according to the dia-gram in Figure 8. Set the line posts 20 feet apart down the row. Brace the end posts as shown.

During the first season, the primaryobjective for grapevine growth is develop-ment of a healthy root system and straighttrunk. After setting the vine, prune it to onestem and cut this stem back to two or threebuds. When new growth begins and the firstshoots from the two-bud cane reach 6 to 10inches in length, select the most vigorousand prune away the others. Tie the shootgently to the training stake several timesduring the first season (Figure 9). Pinch lat-eral shoots back to the leaf growing fromthe main shoot. This allows the main shootto grow more rapidly, possibly saving as

Figure 5. Red raspberry trellis for Dormanred variety. Wires are set at 5 feet abovethe ground. Treated posts are spaced 20 feet apart and set at least 24 inches intothe ground.

A B

Figure 4. An erect blackberry plant (A) before pruning and (B) after pruning.

5’

20’

much as a year in establishing a healthyvine.

Mid-trellis Cordon System (for usewith French hybrid vines such as Seyval andvinifera vines such as Chardonnay andCabernet Sauvignon). Allow the main shootto grow until it reaches 3 feet tall (Figure10). Tie it to the trellis, pinch off the tip, andallow several of the lateral shoots to grow.Begin training in the second year by evaluat-ing the extent of growth achieved during thefirst year. If no cane has reached the firstwire, remove all but one cane. Prune thiscane back to two buds and treat it as a new vine.

In the winter following the first seasonof growth, remove all but a few good canesthe diameter of a pencil. No added trainingis necessary, but it is vital to remove flowerclusters in the second growing season. Vinesthat grew extensively in the first year willlikely have one or more canes suitable forretention as a trunk. If a cane is longenough to reach the lowest trellis wire andis of adequate diameter (approximately 1/2inch), retain the cane as a trunk. The distal(tip) portion of such canes can be trainedhorizontally along the training wire to serveas the basis for a cordon (see Figures 10through 12).

Cordon establishment begins in the sec-ond season of growth and should continueover a two-year period for best results. Toestablish a 3-foot-long cordon, begin with an18-inch cane (or trunk extension) in thesecond year, and complete the cordon in thethird year with another 18-inch cane fromthe distal end of the short cordon (Figures11 and 12). Canes that are used to establishthe cordons should be wrapped looselyaround the trellis wire and tied securely atthe end with wire to prevent the cordonfrom rotating or falling from the wire.

During the second growing season,shoots that develop below the lowest trelliswire should be pruned to one or two budsnear the graft union. Retain 10 or moreshoots that develop on the cordon in thesecond year.

In the third year the cordon systemshould be completed. For the trellis mid-wire cordon, canes that rise from the upperside of the cordon arms should be prunedto one- or two-node spurs (see Figure 12).These spurs should be 4 to 6 inches apart.Develop a second trunk and cordon from acane that originates near the graft union.Keep a small crop of fruit (for example, onecluster for every two shoots) on vines thathad at least 1 pound of cane prunings fromthe second-year growth. Tie shoots to wiresas necessary during the growing season.Treat weak vines as second-year vines andremove all crop.

Cordons may be either unilateral orbilateral; in either case, cordons should ulti-mately span the distance between two adja-cent vines in a row.

High-trellis Cordon System (for use with American bunch grapes andMuscadine). The initial training of the trunk is the same as used with the mid-wire trellis system, but in this system cor-dons are trained along the top wire of thetrellis. Spurs (short canes) are retained onthe lower sides of the cordons to promotedownward growth in American bunch varieties.

Figure 6. Heritage variety raspberries may be allowed to grow untrellised (A), butcrossbar trellising (B) is recommended. Set the crossbars to space the wires 18 to 24 inches apart and about 4 feet above the ground.

Figure 7. Black raspberry plant (A) before and (B) after dormant season pruning.

A B

A B

4’

2’

The vine must be pruned every year toavoid alternate-year bearing and to makeharvesting easier (Figure 13). Pruningmature vines consists of three operations.The first step is pruning last season’sgrowth. In the dormant season, prune backall canes that grew during the previous sum-mer to 4 or 5 inches in length. Leave theremaining spurs at a 6-inch spacing onyoung vines. As the vines age, they will devel-op clusters of spurs. These spurs must bethinned after the third season to force newspur growth. This process also minimizesthe labor necessary for cane tying and keepsfruit and renewal regions at a uniformheight, facilitating harvesting and pruning.The second step is to remove suckers orshoots growing from the trunk and any damaged arms. A new cane must be trained(from the renewal canes at graft unionheight) to replace the removed arm. As thethird step, remove all tendrils that attachthemselves to the trunk or fruiting arm ofthe vine.

Overcropping will greatly reduce fruitquality. Some cluster thinning in years ofheavy fruit set (thinning to one cluster pershoot) is the simplest way to ensure thatthose remaining will develop into larger,more fully ripened clusters. A good rule ofthumb for mature vines is to allow no more

than two clusters per shoot. Excess clustersshould be removed before bloom (early Mayin the piedmont; late May in the mountains).

STRAWBERRIESIn matted-row beds, allow the runners

to establish a bed 18 to 20 inches wide. Thebest spacing within the bed is about 4 to 8inches between plants. Thin the bed to thisspacing if more plants develop. Destroy run-ner plants that root in the row middles andremove all weeds and grass as they appear.

Figure 9. Train the new grape shoot bytwisting it around the training stake as itgrows. Tie it loosely every 8 to 10 inches.

Figure 10. Bilateral cordon training system for grape vines, year 1. (A) Spring, at planting; (B) fall, weak vine at end of growingseason; (C) fall, vigorous vine at end of growing season.

Figure 8. Dimensions for the end post construction for a grape trellis that can be used for either mid-wire or high-wire cordon training systems.

A

Trellis post

Trellis wire

Trellis wire

Trellis wire

End post5” to 7” x 8”

End post5” to 7” x 8”

First line post31/4” to 4” x 7”

Line post31/2” to 4” x 8”

Training stake

B C

4’

5’

3’

48”

5’

3’

Figure 12. Bilateral cordon training system for grapevines, year three. (A) Spring, weak vine after pruning; (B)spring, vigorous vine after pruning.

A B

A B

A B

C

C D

Figure 13. (Below) Completed bilateral cordon trainingsystem for grapes. (A) Mid-wire system for use withFrench vines such as Cabernet Sauvignon and Seyval.Spurs are trained upward. (B) High-wire system for usewith American bunch varieties. Spurs are trained down-ward. Spurs should be pruned to four buds and spaced 4 to 6 inches apart along the cordon. (C) System forMuscadine varieties. This is essentially a high-wire system, but the growth characteristics of these grapes prevent training spurs in a downward direction.Approximately 20 two-bud spurs should be retained for each 10-foot permanent arm (cordon); the spur orientation (upward or downward) is not important inMuscadine training.

Figure 11. Bilateral cordon training system for grape vines, year two. (A) Spring, weak vine after pruning; (B) vigorousvine after pruning; (C) fall, weak vine; (D) fall, vigorous vine.

5 1/2’

5 1/2’

5 1/2’

5 1/2’

Trellis wires

Before pruning

After pruning

Before pruning

Fruiting spur Cordon

After pruning

Trunk

Before pruning

After pruning

3’4 1/2’

10’

HarvestingHarvesting

INSECTS AND DISEASESSatisfactory results in home plantings

can be obtained with very little use, if any,of pesticides. It is best to avoid using themif possible. Maintaining good sanitationpractices goes a long way toward keepingdisease and insect damage under control.Rake up and burn or bury rotten fruit anddead leaves from under plants. Cut off andburn dead and injured twigs, branches, or canes.

Japanese beetles are often the mostserious insect pest, especially on grapes,blackberries, and raspberries. Observe the plants every few days to avoid severedefoliation.

Should a serious problem develop,your county Cooperative Extension agentcan give information on the latest, safest,and most effective chemicals to use. Ready-mixed commercial packages of pesticidescan be purchased under various brandnames, or the separate materials can bepurchased and combined. In either case,read the labels on containers to determine

contents and directions for use.Follow suggestions and directions

carefully with regard to dosage and applica-tion intervals to avoid pesticide residues onthe fruit at harvest.

BIRDSTo keep birds from becoming pests

during the ripening season, cover the plantswith tobacco cloth, cheesecloth, netting, orsimilar materials before the fruit beginsripening. Keep the plants covered complete-ly (except when harvesting) until all thefruit has been picked. At present, this is theonly practical and sure method known tocontrol bird damage in small plantings.

Scaring devices (such as aluminumwhirling devices) sometimes keep birdsaway. If you use them, put them into serviceearly in the season at the first sign of fruitripening and before the birds have becomeestablished in a feeding area. These devicesmust be operated from dawn to dark andmoved around frequently before the birdsbecome accustomed to noise emitted from

a particular location.

WEEDSMany home fruit gardens are too large

for hand weeding and too small for the useof heavy equipment. In many cases, handpulling and mulching can be used to con-trol weeds. Herbicides can supplementthese cultural practices to make the workof controlling weeds easier and faster.

Some chemical manufacturers sell her-bicides in small quantities that are ideal foruse on small areas. These chemicals areformulated to make them more convenientand easier for homeowners to use. Forlarger areas, several products can be pur-chased over the counter at farm chemicalretail stores.

Postemergent materials will kill manyweeds that are already growing. Rememberto keep these materials off the crop plantsto prevent damage. To control germinatingseedlings, several preemergent herbicidesare available. Consult your countyCooperative Extension agent and read alllabels closely.

Pest ManagementPest Management

BLACKBERRIES AND RASPBERRIES

The harvesting of some erect thornyblackberries begins about a week or twoafter the strawberry season (about the first ofJune in Raleigh); semitrailing thornless typesusually do not begin ripening until midsum-mer. Pick when the fruit is dull black inappearance. For raspberries, harvest twice aweek when fully ripe. Pick in the morningwhen the air is cool and berries are firm.

BLUEBERRIESHighbush blueberries begin ripening in

mid-May along the southeastern coastal

plain and early to mid-July in the mountains.Rabbiteye varieties begin about one monthlater. When rabbiteye fruit first turns com-pletely blue, it may still be sour and slightlybitter. Wait at least seven days from the timethe first berries become blue before harvest-ing to ensure acceptable flavor. Harvestevery five to seven days for highbush, every10 days for rabbiteye.

GRAPESOn a vine that has not been over-

cropped, the berries of black varieties willlose their red color, and white varieties willchange from green to golden yellow. Ripe

berries will soften and seeds become brown.For table use, the deciding factor is taste. InNorth Carolina, grapes are generally harvest-ed from July through October. Some vari-eties (such as Carlos) have dry stem scarswhen pulled as individual berries from thevine. Others (such as Noble) should beclipped to prevent wet and leaking scars thatlead to premature spoiling.

STRAWBERRIESPick strawberries every other day or

three times a week. Pick the fruit only whenfully red, with about one-fourth of the stemattached.

Prepared by:E. Barclay Poling, Director of Small Fruit CenterEric B. Bish, Horticultural Extension Associate

Gina E. Fernandez, Horticultural Extension Specialist W. Terry Bland, Horticultural Science Technician

The use of brand names in this publication does not imply endorsement of the products or services named or criticism of similar ones not mentioned.

This document was originally issued in print as AG-588, Grapes & Berries for the Garden,by North Carolina Cooperative Extension Service in June 1999.

Published byNORTH CAROLINA COOPERATIVE EXTENSION SERVICE

Distributed in furtherance of the Acts of Congress of May 8 and June 30, 1914. Employment and program opportunities are offered to all people regardless of race, color,national origin, sex, age, or disability. North Carolina State University, North Carolina A&T State University, U.S. Department of Agriculture, and local governments cooperating.

8/99-5M-DSB (Revised) AG-15E99-35390

College of Agriculture & Life Sciences • NC State UniversitySchool of Agriculture • NC A&T State University