Training and

Trellising Grapes

for Production

in Washington

EB0637

Contents

Different Grape Types

Trellis Systems

New Systems of Trellising

End Posts and Anchorage

Spacing and Vineyard Layout

Training and Pruning Young vines

Training European Varieties for Winter Protection

Summary and Glossary

�

Training and Trellising Grapes for Productionin Washington

by M. Ahmedullah, Ph.D., Associate Horticulturist, Washington State University, Pullman

ThisbulletinprovidesinformationontrainingandtrellisingsystemsincommercialuseinWashington.Othersystemsnotincommercialusewhichhavebeentriedonasmallscalebygrowersorexperimentsta-tionsarealsodiscussed.Mentionofsomeofthenewersystemsdoesnotmeanthattheyarerecommendedtothegrowers.

Different Grape Types TwotypesofgrapesaregrowncommerciallyinWashingtonstate:

1) Americangrapes,Vitis labruscaand

2) EuropeangrapesVitis vinifera.American grapesrepresentedbythecultivarConcord areusedprimarilyforjuicemaking.

AsmallacreagesupportsthevarietyNiagara,awhitelabruscatype.Elevencultivarsofviniferagrapesareusedexclusivelyformakingwine.AnothersmallacreagegrowsEuropeantypetablegrapes,whichareharvestedbyhand.Almostalllabruscagrapesaremechanicallyharvested.Manyviniferatypesalsoareharvestedmechanically.Takemechanicalharvestingintoconsiderationwhendesigningtrellisingandtrainingsystemsforgrapes. Thegrapevinedoesnothavearigidtrunk;there-fore,somesupportstructure,usuallyatrellis,mustbe

provided.Thetrellisdesignshouldprovidemaximumlightpenetrationforthebudsandclusters,especiallyinthelaterpartofthegrowingseason,whileexposingalargepercentageoftheleavestosunlight.Thegrapetrellisisamajorlong-terminvestment.Beforedesign-ingatrellis,growersmustconsiderallthosefactorsthatmayaffectvinegrowthandmanagement,e.g.,irrigationsystems,variety,vinevigor,mechanicalpruning,andmechanicalharvesting. Agoodtrellisshouldhavesomeormostofthefol-lowingcharacteristics:

l) strongandlong-lived;

2) supportsthetrunk,cordons,arms,spur,canes, andfoliage;

3) providesthemaximumexposure ofleavesandbudstosunlight;

4) economicaltoconstruct;

5) easytorepairandmaintain;

6) permanentwithlittleneedforannual maintenance;and

7) adaptabletomodernmechanicalpruning andharvestingmachines.

SeveralkindsoftrellisesandtrainingsystemsareinuseinWashington.Growersaretryingnewones.Primarydifferencesamongtheseareinheight,numberandlocationofwires,useofhorizontalwirespreaders,flexible extended arms, posts for support of wires, end posts,andanchorageforendposts.

�

Trellis SystemsSingle wire system

Seven-footpostshavingaminimumtopdiameter of3to4inchesarespacedabout18to21feetapart(everythreeplants).Linepostsmustbeburiedatleast 2feetinthegroundforadequatesupport.Asingle#9wireisthenplacedacrossthetopofthepost,5feetabovetheground(Figure1).Grapesarecordontrainedalongthiswireinbothdirections.TheyalsocanbecaneprunedbutthisisnotcommoninWashington.

Thissystemisleastexpensiveofalltrellisingsystems.Itisadaptedtomechanicalharvesting,andisusedforConcordgrapes.Itdoesnotofferfullexposureoffoliagetosunlightforvigorousvarieties.

Two‑wire vertical trellis

Thelinepostshaveatopdiameterof3to4inches.Theyare7feetlong,placed18to21feetapart.As inthesinglewiresystem,thelinepostsshouldextend atleast2feetintotheground.Thetopwireisplacedacrossthetopofthepostwiththesecondwireplaced 30to36incheslower(Figure2).Theheightofthesecondwireshouldnotbesolowthatfruitcannotbepickedduringmechanicalharvesting.Thevinesarebi-lateralcordontrainedonthetopwire.Thebottomwireisusedfortrainingtwocanesoneithersideofthetrunk.This system, sometimes known as the Kniffin system, is usedforConcordgrapesinWashington.

Atwo-wireverticaltrellissystemiscommonlyusedforviniferagrapes.Putthetopwireontopofthepost5feetabovegroundlevel.Thisisreferredtoasthefoli-agewire.Number11wireisusedforfoliagewire.Forcordonsupport,placeasecondwire(#9wire)16inchesbelowthetopwireand44inchesabovegroundlevel.

Figure 2. Two-wire vertical trellis, vines bilateral cordon trained.

Figure 1. Single wire system.

3

Two‑wire multiple trunk system

Thissystemisnotpracticedcommerciallytodaybecauseoftheextraexpenseinvolved.However,someinterestexistsinthissystembecauseofseverewinterdamagetoviniferagrapesinlessdesirablesites.Insteadofasingletrunk,multipletrunksareallowedtodevelopforviniferagrapes.Thearmsandcanesareremovedfromthetrelliseachfallandcoveredwithsoilforwinterprotection (Figure 2a). In this kind of training five canes serve as flexible trunks. The trunks are tied up on the wireforsupport.Earlierplantingsofviniferagrapeswerestartedwiththissystem.

“T” Trellis

Thewiresofthe“T”trellisareparallel.Theyareseparatedandsupportedbyacrossarmattachedtothepost.Thisprovidesforbetteruseofsunlight.Inthisthree-wiresystem,thecenterwireislocatedonthe8-footlinepostsapproximately5feetabovethesurfaceoftheground.A3-to4-footwoodenormetalcrossarmisattachedacrossthetopofthepost(6feetabovetheground).Thetwoparallelwiresattachtoeachendofthecrossarmtosupportthefruitingcanes.A#12wire isusedforthecenterandtwo#9wiresareusedateachendofthecrossarm(Figure3).Giventheuseofmechanicalharvestersforviniferagrapes,theuseofametalcrossarmisbecomingverypopular.

Theprincipaladvantageofthe“T”trellisisgreaterexposureoffoliagetosunlight.The disadvantage has been the difficulty of adaptingthissystemtomechanicalharvesting.Whereproperadjustmentsaremadeinharvestingmachines,however,thissystemhasbeenwelladaptedbymanygrowers.ItcanbeusedbothforConcordandviniferagrapes.Thecostofinstallationishigherthanthesinglewireandtwo-wireverticalsystems.

Forviniferagrapes,placethelowerormainwire41/2feet(54inches)abovethegroundtocarrythemainarmsofthevine.Placethe2-foot-longcrossarmevenwiththetopofthepost,6feetabovetheground.Threewiresarepositionedonthiscrossarm.Sincetheirpur-poseistosupportonlythenonfruitinggrowth,theycanbe#12wires.Wiresareplacedontheendsofthe2-footcrossarmandathirdwireattachedtothetopofthelineposts.Thislatterwirepreventsyoungshootsfrombeingblownbythewindononesideofthetrellisduringtheirearlygrowth.

Figure 2a. Multiple trunk (Fan) training of vinifera cultivars on a two-wire

vertical trellis.

Figure 3. “T” trellis, vines are bilateral cordon trained.

1-to 3-year-oldtrunks (flexible)

�

Geneva Double Curtain (GDC)

ThistrainingsystemwasdevelopedbyresearchersoftheGenevaAgriculturalExperimentStation,CornellUniversity,NewYork.Inthissystem,thenumberofgrapeleavesthatareeffectivelyexposedtosunlightareconsiderablygreaterthaninthesinglecurtaintrainingsystems.

IntheGDCsystem,thelengthofcordonsperrowisdoubled.Thisexposesleavesonagreaternumberofshootsattheirbasalfourtosixnodestosunlight.Thisisachievedwithshootpositioning,apracticecommonlyadoptedinNewYorkbutnotinWashingtonstate.Forbetteradaptationtothissystem,thevinesshouldbevigorouswithadroopingshootgrowthhabit.However,cultivarsnothavingthesecharacteristicsalsohavebeentrainedtotheGDCtrainingsystemwitheconomicallysignificant yield increases.

Thissystemrequiresathree-wiretrellis,usingtwohorizontalcordon-supportwiresandalowersingletrunksupportwire(Figure4).Thecordonsupportwiresareplaced6feetabovethegroundand31/2to4feetapart.

ForestablishingvinesforGDC,elongatedtrunksarepassedbehindandlooselysecuredtothelower

trunk-supportwirewithtwineorplasticties.Astheygrow,thesearebroughtupandouttoacordon-supportwireandtiedtokeeptheminposition.Thecordonsareformedbyselectingshootsfromthetrunksgoinginop-positedirectionsalongthecordonsupportwire.Thecor-donsoneitherdirectionshouldbeheldincontactwiththecordonwirebywrappingthemaroundsupportwiretwotofourwrapsevery6to8feetofcordon.Insteadofwrappingaroundthewire,thecordonsalsocanbetiedwithstringorplasticties.

Thevinesintherowusuallyarealternatedtotheleftorrighttowardsthecordonsupportwiretogivethedoublecurtaineffect.Afterestablishingthehorizontalcordons,growersallow10-to12-footequallyspaced,preferablydownwardgrowingverticalarmspervinetodevelop.Selectionofthesearmsisveryimportantifshootpositioningispracticed,asthefruitingcaneswilloriginatefromthesearms.Selectionoftherightarmsconsiderablycutsbothlaborandcostinfuturemainte-nanceofcordonsandforshootpositioning.

Thecordonsupportwiresshouldbeofgoodqual-itysteel.Usuallya#10or#11wireisusedforcordonsupportanda#11or#12wireforthelowerwirefortrunksupport.Keepthecordonsupportwirestaut.Forefficient mechanical harvesting the fruiting cane area shouldbe5to51/2feetabovetheground.

Figure 4. Double curtain trellis with bilateral cordon training.

�

New Systems of Trellising

Wye “Y” System

Forestablishingthetrellisinthe“Y”system,plantsturdyposts3feetinthegroundand3to4feetaboveground.Nailandbracetwopoststotheverticalpostatapproximatelya45-degreeangle,oneoneithersideoftheverticalpost.Acrossbarjoiningtheverticalpostandthetwoslantingpostsprovidesstrengthtotheframework.Fortrainingthevines,headthematabout3feetfromthegroundlevel.Thisshouldgiverisetobranchingofthemaintrunk.Bringthetwobestshootsatrightanglestotherowtoforma‘’Y.’’Thesetwoshootswillformthearmsofthe“Y.”Fromthetipsofthe“Y”asecondheadisestablished.Fromeachoftheseheadstwocordonsaredevelopedparalleltotherow.Afour-armedcordon(Quadrilateral)isthusestablished(Figure5).

Forbestresultswiththissystemadistanceof4feetbetweenthewiresisneeded.Closerdistances(3feet)donotallowenoughpenetrationofsunlight,resultinginshading.Thewiresshouldbe5to51/2feetfromthegroundlevel(Figure5).ItismoresuitedtovigorouscultivarslikeSauvignonblanc.ThesystemhasbeentriedinCaliforniaonalimitedscale.MoreexperienceisneededwiththissystemunderWashington’sgrowingconditions.

ThechiefdisadvantageofthissystemisthatwiththemechanicalharvestingmachinesavailableinWashingtonandCalifornia,fruitcannotbemechanicallyharvested.Thehighercostofestablishingavineyardwiththissys-temisanotherfactor.

Gable Trellis

ToconstructaGabletabletrellis,plantlineposts (3feetinthegroundand3to4feetaboveground)intherow30feetapart.Theoverheadsupportisprovidedbyplacingpolesfromeachlinepostata45-degreeangle.Theoverheadpostsarenotnormallytreated.Theendsofthepostsmeetinthemiddleoftherow12feetfromgroundlevel.Whencompleted,thestructureresemblesacontinuous“teepee”orangularoverheadarbor.

Thesystemuses10hightensilewireshavingaguaranteedbreakingstrengthof1,860pounds;thesearestapledtooverheadbars.Thewiresinthegablesystemaretensionedattheendat250poundswheninuse.Thus,for10wiresacombinedlateralpullof2,500poundsisneededateachanchor.Theanchorposts,therefore,havetobeverysturdy.Forthisreason,a9-footanchorpostisneeded.Fivefeetofthisanchorisdrivenintotheground.Thelineandendpostsinthegablesystemarecustomdriven.Toeachlinepost,over-headsareattachedwithapinmadefromsmoothrebar.Boththelinepostandoverheadaredrilledusingabenchdrill(Figure6).Highlaborcostsmakethisaveryexpensiveoperation.

Theadvantageofthegablesystemoverthebilateralcordonsystemisthatitcanexposemoreleafareatothesun,thusincreasingthephotosyntheticcapacityofgrapevine.Sincethistrellisisaninverted“V”shape,shadingisminimizedbothinthemorningandafternoonhours.

Thegablesystemhastwomaindisadvantages: 1)itcostsconsiderablymorethanthebilateralcordonsystem,2)itdoesnotlenditselftomachineharvestingwiththemachinespres-entlyinuseforgrapesinWashingtonandCalifornia.

Figure 5. Wye “Y” System.

Figure 6. Gable System.

6

Sloping Arm

Toconstructthe“Slopingarm”trellis,driveaverticalpostintotheground3feetwith3feetremainingabovetheground.Nailandbraceawoodenarmata35-degreeangletotheverticalpost.Thearmshouldprojectabout9feetfromtheverticalpost.Seventoninewiresarestapled12inchesfromeachother.

Plantandtrainthevinealongtheverticalpost.Whenitreachestheheightoftheslopingarm,theshootsareallowedtogrowonthewiresonthearm.Theshootscompletelycoverthecanopywhenfullygrown.

ThissystemwasintroducedintotheUnitedStatesfrontSouthAfrica,whereveryhighyieldshavebeenobtainedwiththissystemduetogreaterexposureoftheleavestothesun.Thissystemismoreexpensivetobuildthanthetwo-wireverticalsystem.Itisnotpossibletousemechanicalharvesterswiththeslopingarmtrel-lis.Becauseofthegreaternumberofwiresused,thissystemalsoismoreexpensivetomaintain.

Grape Arbors

Researchandcommercialplantingsincertainpartsoftheworldhavedemonstratedtheimportanceofobtainingmaximumexposureofgrapefoliagetolight.Grapearborsfacilitatethisexposure.Theycanbeconstructedasdoubleormultiplerowarbors.Grapesare trained on cross wires from posts sufficiently high to facilitateoperatingequipmentbeneaththecrosswires.

Whilehighyieldsareobtainedfromsuchstruc-tures,thestructuresareexpensivetoerectandmaintain.Theyalsorequirealongerunproductiveperiodbetweenplantingandcommercialharvest—adelayof2ormoreyears—whilethevinesmatureandaretrainedoutontocross wires. Two other disadvantages are the difficulty inpruningandthelackofadaptabilitytopresentme-chanicalharvestingsystems.

End Posts and Anchorage

Whethergrapesaretobegrownonverticaltrellises,“T”trellises,ordoublecurtaintrellises,secureanchor-ageofpostsandwiresisveryimportant.Considerationsaretheheightandweightofthevines,resistancetowind,theweightofthefruit,andstressesfrommechani-calharvesting.Manynewertrellisingsystemsaresig-nificantly increasing the tonnage of fruit to be supported.

Recordsofover20tonsperacre(60to70poundsoffruitpervine)havebeenexperienced.Evenasmallgiveorshiftingoftheendpostscanpreventmechanicalharvestingorcauseexpensivedelays.Variousmeanshavebeentakentodevelopadequateanchorage.Someofthesefollow.

Figure 7. Sloping.

7

“H” System

Thissystemiscommonlyusedinfencing(Figure.8a).Twopostsaresetatleast6feetapartwithahorizontalcrossmemberplaced12inchesfromthetopoftheposts.A#9wireisthendoubledandwoundbetweenthebaseoftheendpostandthetopoftheinnerpostandtightenedbytwistingwithanironrodora1x2-inchpieceofwoodandlockingbehindthenearestpostorcrossmember.Thispreventsthebracewirefromunwindingandalsopreventsthetendencyoftheendposttoloosenandliftoutoftheground.

Inverted “V”

Thissystemiscommonlyusedforhightrellisesandarbors(Figure8b).Itconsistsofa9-foot-longendpost,setatapproximatelya60-degreeangleratherthanupright,withthebasesetabout3feetintotheground.Thetopofthepostisthentiedwithheavywiretoalarge“deadman”placed3feetintotheground.

Thesystemisstrongandwillresistconsiderablepullwhenprop-erlyconstructed.Failuresareexperiencediftheangleofthepullonthe“deadman”isoverlyvertical.Placingthe“deadman”outfarthersothewirepullsatmoteofa60-degreeanglereducesthehazardofalift.

Asecondweaknessinthissystemiscorrosionofthewireatthegroundline.Thisproblemcanbereducedbyutilizingasteelrodfromthe“deadman”toaboutafootabovetheground.Thewireisthenattachedtotherodinsteadofdirectlytothe“deadman.”Coveringtheportionofthewirethatistobeexposedtothesoilwithtarwouldpreventdete-riorationbyrusting.

Anchoring of Vertical End Posts

Increasinglaborcostshavecausedgrowerstoseeklessexpensivewaystoanchortrellises.Insteadofmanuallysettingendpostsonanangle,theycandrivethemvertically,astheremainderofthevineyard,andanchorthembyarodorheavywireata45-degreeangle(Figure8c).Rock,concreteblock,pouredconcrete,orasizablemetalobjectcanbeburiedinthegroundforanchoring.Inrock-freesoil,a5-inchsquareofmetalplate,cutdiagonallyandspread1/2inchatthecornersandfixed to a metal rod (60 x 5/8 inches), can be turned into the soil at a 45-degreeanglewithatractorpowertake-off,hydraulicmotor,orheavydutyelectricdrill.

Thedisadvantageofthisanchoringsystemisthevulnerabilityofthesupportingwiretodamagebyvineyardequipment.Tominimizethishazard,driveamarkerpostwherethewireentersthesoil.

Figure 8. Anchoring systems.

�

Spacing and Vineyard Layout

Severalspacingsareofconcernwhenestablish-ingavineyard.Mostobviousisthedistancebetweenrowsandplants.Experiencehasshownthatthedistanceallowedforturningequipmentattheendsoftherows,spacingofpostsandbracingwires,andlengthofrowscanbeequallyasimportant.

Row Arrangement and Distance

Mechanicalharvestinghasemphasizedthedesirabilityofrelativelylongrowsrequiringfewturns.Harvesterscanaccommodatesomeslightdifferencesintopographybutdonottraversesteepslopesreadilyastheyworkupanddownhillsides.Breaklongrowsintoabout600feetbetweenendposts.Greaterdistancescre-ateincreasedstressonendsupports.Also,theytendtocreatemoresaginthewireasthemechanicalharvesterswork.

Headlands

Mechanicalharvestersrequireaminimumturningradiusof20feet.Topreventequipmentfromstrikingendpostsandguidewires,moreroomispreferred.CAUTION:Whereguidewiresextendbeyondtheendposts,makecertaintheavailableheadlandsaremeasuredtotakethisfactorintoaccount.

Row Spacing

Plant rows sufficiently close to make maximum use of the land but sufficiently wide to facilitate operation of equipment.Ingeneral,equipmentrequires7feetoffreespace.Ifanuprighttrellisisused,thedistancebetweenrowsshouldbenolessthan9feet.Whenusingadoublecurtainor“T”trellis,whererowwidthisincreased,thedistancebetweenrowsmaybeincreasedto10feet.

Rows9feetapartcanaccommodatedoublecurtains3feetapartplaced66inchesabovegroundlevel.However,accuraterowspacingandtrelliswiresplaced

atleast70inchesabovegroundlevelarenecessaryifdoublecurtains4feetapartareusedonrowsspaced9feetapart.Doublecurtains4feetapartcouldbeplaced51/2feetabovegroundlevelifrowsarespaced10feetapart.Thedecisioninvolvedinrowspacingandtrellisheightistobeabletooperatevineyardequipmenteitherbetweenthecurtainsoffoliageorbeneaththem.

Plant and Post Spacing

Thedistancebetweenplantsdeterminesthespacingofposts.Ingeneral,adistanceof18to21feetbetweenlinepostsreducesthesaggingofwirestothatwhichcanbetoleratedbymechanicalharvestingdevices.Distancebetweenplantsdependsuponsoilandplantvigoraswellastrainingpattern.Adistanceof8feetiscommonwithAmerican-typegrapesbutmaybereducedtoaslowas6feetonsandy,lessfertilesoilsandex-pandedto9feetwithvigorousEuropean-typegrapesongoodsoil.

Number of Plants per Acre

Thenumberofplantsperacreofgroundvariesac-cordingtoplantingdistance,breaks,andheadspace.Aguidetothenumberofplantsrequiredfortheactualspaceplantedfollows:

Number of Plants

�07 69� 60� 7�6 6�� ��� ��� 660 �66 �9� ��0 396

Planting Distance 6 x 9 7 x 9 � x 9 6 x �0 7 x �0 � x �0 9 x �0 6 x �� 7 x �� � x �� 9 x �� �0 x ��

9

Training and Pruning Young Vines

Asindicatedunderthediscussionofsystemsoftrellising,anumberoftrainingsystemsexist.ExceptwhereEuropean-typegrapesaretobetakendownandcoveredwithsoilforwinterprotection,youngvinesarehandled in much the same manner for the first 3 to 4 years.

First Year—Year of Planting

Afterplanting,cutbacktheyoungplanttothetwobestbasalbuds(Figure9a).Iftheshootsgrowvigorouslythatsummer,trainthestrongestupastakeorahempstringtothewire(s)onthetrellisfordevelopingatrunk.Pinchbacktheremaininggrowthtoencouragemaximumdevelopmentoftheselectedshoot.However,the labor required the first year to train grapes is usually tooexcessivetobepractical.

Second Year—Year After Planting

Duringthedormantseason,ifashootwasnotselectedandtrainedtheprevioussummer,selectthebestpositionedcaneandtieitsecurelytothetopwire(Figure9b).Ifthecaneistooshort,tiethestringjustbelowthebesttopbudandextendtothetopwireandsecure.Asshootsdevelop,retainthetoptwothatarelocated6to9inchesbelowthewire.Thesearetobetrainedeachwayalongthewirefordevelopingeithercordonsorshortarmsforbearingcanes.Removeaxil-laryshoots(newlateralshootsatbaseofleaf)thatde-velopbelowthislevelwhilesmall.SummerpruninginJulyandlaterlimitsvinesizeanddelaysvinematurity.

Ifthecanegrowthistoosmall(lessthan36incheslongandlessthan1/4inchindiameter)cutbackallgrowthtotwobudsnearthebaseofthebestcaneandtrainasdescribedabove.

With the Kniffin system, train one strong new shoot verticallytotheupperwire,selectinglateralstotraineachwayonbothwiresaftertheshoothasbeentipped6inchesbelowthetopwire.Useahemporcomparablestrengthstringfortraining.However,tie

iteithertoastakeatthebaseofthevineortothevinewithalargenonsliplooptoavoidgirdling.Removeten-drilsaroundthetrunk,armsorcanesthataretobecomepermanentpartsofthevinetopreventgirdling.

Figure 9. Care of young vines the first three years in the vineyard.

A First Year

B Second Year

C Third Year

�0

Third Year

Continuetheprocessoftrainingthevines.Placethecaneslaterallyineachdirectiontooccupytheone-ortwo-wiresystemselected(Figure9c).

Placecanestrainedforarms(cordons)bilaterallyon a single wire system first over the windward (west or south)sideofthewireandwrapatleastonecompleteturn.Securecanestothewirewithloosetiesatthepointof first contact, at mid-point along the wire, and more tightlybackoftheendbud.

For the double curtain system, first place the canes fordevelopingthecordonsoverthewireandwrapatleastonecompleteturnandtieasforthesinglewire.

CAUTION:Becauseofthetendencyofyoung vinestooverfruit,donotretainover20to30buds onthemostvigorousvines.Overproductionatthis agecanreducepotentialproductionoverthenext 2or3years.

Ifcaneshavenotreachedthisstageofdevelopment,followproceduresdescribedaboveforyoungervines.

Fourth Year and Later Years

Ifcordontrainingisdesired,retainthecanesthatproducedthecropthethirdyearforfuturecordons.Cutthecanegrowthonthecordonalternatelytoone-budandfour-budcanes.Fillinvacantwireareasbyextend-ingcanesfromtheendofthecordon.Removeothercanes.One-ortwo-budcanesareretainedonspur-prunedEuropeanvarieties.

Forlongcanetrainingonasinglewire,leavetwocaneswithtwobudseachforrenewalsatthebaseadja-centtothetrunkandfour6-to8-budcanesfartheroutforfruiting.Traintwocaneseachinoppositedirections.If a two-wire system is used, as with the Kniffin system (Figure1),selecttwocanesforthetopwireandoneortwoforthebottomwire.Leaverenewalbudsateachlevelonthearmnearthetrunk.

Training European Varieties for Winter Protection

First Year—Year of Planting

Afterplanting,cutbacktheyoungplanttothetwobestbasalbudsontwoorthreecanes.Letshootgrowthdevelopwithnofurthertraining.Hillbaseoftheplantwithahillingdiskattheendofthegrowingseason.

Second Year—Year After Planting

Trainonetothreeofthebestcanesuponthetwo-wire Kniffin type trellis with the canes distributed uprightinafanlikepositionandtieinplace.Pruneothercanesoriginatingatthegroundleveltoonebud.Attheendofthegrowingseason,prunelateralsonetofive buds long on canes that developed the first year. Retainoneortwoadditionalcanesthathavedeveloped.Leavenomorethanatotalof20to30buds.Remove

allarmsandcanesfromthewires,holdinginplaceonthesoilsurfacewithnotched1x4-inchboardswedgedunderthelowerwire.Thecanesandarmsplacedonthegroundarecoveredwithsoilbydrivingonbothsidesoftherowwithaterracingdisk.Removewedgingmateri-alsandproceedtothenextrow.

Third Year and Thereafter

Removemostofthesoilcoveringthevineswithagrapehoeinlatewinter.Forkoutarmsandcanesandshakefreeofsoil.Tieuptwotothreearmsandcanesonthetwo-wiresysteminafanposition.

Attheendofthegrowingseason(November)andthereafter, prune and cover three to five canes and arms.

��

Balance Pruning Mature Vine

Toachievemaximumproductionfromavine,adjustpruningandfruitingaccordingtovinevigor.Themorevigorousthevine,thelargerthenumber ofbudswhichcanbelefttofruit.Weakervinesmustbeprunedmoreheavilytopreventovercroppingandfurtherweakening.

Thisrelationshipbetweenvinevigorandthecapacitytobearfruitandproperlymatureboththecropandshootsinthefalliscalled“balancepruning.”Itisbasedontheamountorweightofwoodprunedfromthevine.WhengrowingtheConcordvariety,thisbalancebetweencanepruning,weightoftheprunings,andyieldhasbeenestablishedatthelevelof“50+10”.Thismeans that for the first pound of prunings removed, 50 budsareleftonthevine.Foreachadditionalpound,10additionalbudsareretained.Anexampleofitsusewithavineproducing3.2poundsofpruningsfollows:

lst pound .............................................. �0 buds left

�nd pound ........................... �0 additional buds left

3rd pound ............................ �0 additional buds left

0.� pound .............................. � additional buds left

3.� total pounds ................... 7� buds left

Aproportionateamountof50budsisretainedifthepruningweightislessthanlpound.

MostotherAmericanvarietiesrespondwellatapproximatelythesamepruninglevelashasbeendescribedforConcord.WhengrowingEuropeanvariet-ies,prunevinesmoreseverelyaccordingtothevigor.Satisfactoryyieldsandvinegrowthhavebeenobtainedbybalancepruningatabudlevelof10+10inCalifornia.

Summary

Differenttypesoftrellisstructuresforsupport-ingvinesvaryintypeofmaterialusedandtherelativeexposureofleavestosun.Themostcommonincoldcli-matesisthesimpleone-ortwo-wireverticaltypetrellis.Duetotheuseoffewerwiresandsimplicityofdesign,itistheleastexpensive.Thenewersystems,especiallythoseusingmetalstakesand“T”typetrellisdesign,arebecomingpopularbecausetheyofferdistinctadvantagesinmachineharvesting.

Thenewtrellisesdiscussedinthisbulletinhavetheadvantageofincreasedyieldandbetterexposureofleavestosunlight,buttheyaremoreexpensivetobuild.Theyhavethepotentialofconsiderableincreasein yield but have not been tried sufficiently in the colder climates.Considerallfactorsdiscussedinthisbulletinbeforeattemptingtoestablishthevineyardwiththenewsystems.

In the Pacific Northwest where low winter tem-peraturesarecommon,keepyieldsatmoderatelevelstominimizewinterdamage.Veryhighyieldsobtainedwithsomeofthenewersystemsoftrainingandtrellisingarea risky proposition in the Pacific Northwest.

��

Glossary of Terms

Anumberoftermsareusedtodescribeportionsorlocationsongrapeplants.Someofthemareusedinthediscussionof the trellising and training of grapes. The following definitions may be helpful.

TRUNK: Permanent aboveground stem of the vine.

ARMS: Major short branches of the trunk from which canes develop.

CORDON: A long arm, usually trained along a wire, from which canes develop.

CANE: A matured shoot after leaf fall.

SPUR: A cane pruned back to one, two, or three nodes.

SHOOT: New green growth with leaves, developing from a bud of a cane or spur.

LATERAL: A branch of a shoot.

NODE: The thickened portion of the shoot or cane where the leaf and its compound bud are located.

INTERNODE: The portion of the shoot or cane between two nodes.

BUD: A compound bud or eye containing the primary, secondary, and tertiary buds located in the axil or each leaf.

TENDRIL: A long, slender, curled structure borne at some of the nodes of a shoot that can firmly attach the shoot to other shoots and the trellis system.

M. Ahmedullah, Ph.D., Washington State University horticulturist, WSU Pullman.

College of Agricultural, Human, and Natural Resource Sciences

WSU Extension bulletins contain material written and produced for public distribution.

You may reprint written material, provided you do not use it to endorse a commercial product.

Alternate formats of our educational materials are available upon request for persons with disabilities.

Please contact the Information Department, College of Agricultural, Human, and Natural

Resource Sciences, Washington State University for more information.

Issued by Washington State University Extension and the U.S. Department of Agriculture in

furtherance of the Acts of May � and June 30, �9��. Extension programs and policies are consistent with federal and state laws and regulations on nondiscrimination regarding race, sex, religion,

age, color, creed, national or ethnic origin; physical, mental, or sensory disability; marital status,

sexual orientation, and status as a Vietnam‑era or disabled veteran. Evidence of noncompliance may be reported through your local Extension office. Trade names have been used to simplify

information; no endorsement is intended.Reprinted March �996.

Subject code �3�. BEB0637