Pruning and Training Fruit Trees in the Home Landscape · Pruning and Training Fruit Trees ......
Transcript of Pruning and Training Fruit Trees in the Home Landscape · Pruning and Training Fruit Trees ......
PruningandTrainingFruitTreesintheHomeLandscape
WesleyR.Autio1,WinfredP.Cowgill,Jr.2,andJonM.Clements11University of Massachusetts and 2Rutgers University
Deciduousfruittreeshavelongbeenapartofthehomelandscape.Thegraceofthetreeand
beautyofthebloommakethemveryattractiveplants,butthetasteoffreshfruitfromawellmanagedfruittreeisunsurpassed.Unfortunately,however,fruittreesprovideseveralhorticulturalchallenges,asignificantonebeingtreetraining.Weuse“training”ratherthanorinadditionto“pruning”toreflect
thewidevarietyoftechniquesthatshouldbeusedtomanageboththevegetative(shootsandleaves)andthereproductive(flowersandfruit)growthofthetree.
Becauseofthebrevityofthispublication,wewillconcentrateontwospeciesoftreefruit,applesandpeaches.They,generally,typifytwocategories:treeswhichflowerandfruitlargelyonspurs
originatingon2‐yearorolderwood(apples,pears,plums,apricots,andcherries)andtreeswhichflowerandfruiton1‐year‐oldwood(thatwhichwasproducedlastyear)only(peaches).
General Considerations
Whypruneandtrain?Adesirablefruittreeinthelandscapeisonewhichproduceshighqualityfruitannually,isstructurallysound,andisaestheticallypleasing.Pruningandtrainingareusedtoenhancelightpenetrationintothetreecanopyandasaresultcausethetreetoproducelargeandtasty
fruitthroughout.Pruningandtrainingareusedtoincreasebranchstrengthandeliminateweakbranchessothattheresultingcanopyiscapableofcarryingafruitcropwithoutlimbbreakage.Bothpruningandtrainingalsoareusedtomaintainthetreecanopyintheavailablespaceandtomakethat
themostvisuallypleasingtreepossible.Beawarethattheremaysometimesbeaconflictbetweenoptimalfruitproductionandaesthetics.
Tools.Pruningoffruittreesrequiresthreeprimarytools(seeFigure1).Bypasshandprunersareanecessity.Goodqualitypruners,suchasFelcoorPica,shouldcostbetween$35and$60.Youalso
shouldhaveapairofbypassloppers(24‐26”)withanicelycurvedhookontheblade.Barnell,Corona,andBahcoproduceloppersinthiscategorycostbetween$45and$100.
Thelasttoolisagoodsaw.Ourfavoriteisa13”curvedbladepruningsawwithaJapanese‐styleblade(Tri‐cut,TigerTooth,TurboCut,etc.).Thisisapullsawwithaverysharpbladeand
costsbetween$20and$30.Itisbestalsotopurchaseasheathorscabbardforthesawtobothprotectthebladeandyoufromtheblade($20to$30).
Seasonofpruning.Pruningisbestdoneondrydaysinthelatewinterorearlyspring.Apples,
Figure1.Basictree‐fruitpruningtools.
however,canbeprunedaslateasearlyJunewithnoilleffects.Watersproutscanberemovedinmid‐summer.Removaloflargerbranchesinthesummer,fall,orearlywintergreatlyenhancetheoddsof
winterdamage,sincepruningisphysiologicallystimulatingtothetreeandreduceshardening.Peachesareverysensitivetotrunkdiseases,sopruningisbesttimedtooccurintheearlyspring,nearbloom.Atthistimeofyear,thetree’smetabolismisactiveandtreesareabletohealthedamagequickly.
Pruning and Training Apple Trees
Asnotedabove,appletreesflowerandfruitonspursborneon2‐year‐oldandolderwood.Thegreatestnumberandhighestqualityfruitareproduced
onwoodthatisbetween3‐and4‐yearsold.Pruningandtrainingeffortsarefocusedonmaximizingtheamountoffruitfulwoodinatreeandprovidingtheconditionswherethiswoodcanproducefruitofhigheatingquality.Much
researchandexperiencehasshownthattheeasiesttreeformwithwhichtoattainthesegoalsisacentralleader,atreewithasingletrunkandgenerallyaconicalshape(seeFigure2).Wewilldetailafewoftheapproachesnecessaryto
obtainandmaintaintheidealtree.
Topruneornottoprune!Withayoung,newlyplantedtree,itisimportanttoavoidpruningasmuchaspossible.Pruningwilldelaytheonsetoffloweringandfruiting,anditwillreducetheamountoffruitobtainedearlyinthe
lifeofthetree.Thisisnottosaythatyoushouldavoidworkingwithyournewlyplantedtree.Thisisthetime,instead,whenyouwillrelyonothertechniquestomanagethegrowthofthetree.
Limbbending.Itisamazinghowmuchthelimbanglefromthetrunkcanaffectthegrowthandfruitingofthatlimb.
Itstartswhenthelimbisverysmall.Movingtheyounglimbsothatithasabouta90oanglefromthetrunkwillensurethatitwillhaveastrongconnectiontothattrunk,onethatwillnot
breakunderseveralpoundsoffruit.Thebesttimetoestablishthisangleiswhentheshootisabout6incheslong,maybesometimeinlateMayorearlyJune.Thisangleis
easilysetwithaclothespinclampedontothetrunkabovetheshoot(seeFigure3).
Afterastrong“crotchangle”isestablished,limbbendingisusedto
altervegetativegrowthandflowering/fruiting.Morespecifically,alimbgrowingverticallywillproduceaverystronggrowth,mostlyfromthetipbuds,andverylittlefruit.Onegrowinghorizontally,ontheotherhand,willproduce
onlyasmallamountofgrowthdistributedthroughoutthebranchandwillproducemanymorefruit.Adjustingtheanglebetweenverticalandhorizontal
(orevenbelowhorizontal)allowyoutomanipulategrowthandfruiting(see
Figure3.Woodenclothespinusedtomaintainawideanglebetweenthebranchandthetrunk(attheendoftheseason).
Figure4.Limbanglecanaffectbothshootgrowthandfruiting.
Figure2.Conicalshapeofacentral‐leaderappletree.
Figure4).Ingeneral,aconicallyshapedtreecanbeobtainedbymaintaininglowerbranchesinclinedat
about45oandupperbrancheshorizontalordeclinedby10‐20o.Thisapproachcanresultinthedevelopmentofaconicalshapewithoutpruning.It
isimportanttorealizethatthevigorofatreeisnaturallygreateratthetopthanthebottom,soifyousettheanglesthroughoutthetreetothesame
angle,thestrongestbrancheswillbeatthetopandtheweakestatthebottom(seeFigure5).Limbbendingcanbeperformedwithanyapproachwhich
givesthedesiredresults.Popularapproachesincludetyingwithstringorrubberbands,weights,spacingwithsticksorwires.
Pruning.Whenatreebeginstomature,pruningbecomesamoreimportantpartofthetraining
process.Itisdifficulttogiveafulldescriptionoftheartandscienceofpruning.Instead,wewillgiveyousevenbasicrulestofollowasyoupruningyourtrees.Beforewediscussrules,realizethatexposureoftheinnerpartofthetreecanopytosunlightiscriticalforthedevelopmentofflowerbuds,and
trainingandpruningshouldstrivetomaximizetheamountofsunlightinterceptedbythetree.Shadeisyourenemy!Rememberalsothatnewshootsgrownthisseasonwillproduceflowerbudsnextseason,whichwillbloomandhopefullyproducefruitinthenextseason.Sevenrules:
1. Remove2or3ofthelargestlimbsitnthetoptwothirdsofthe
tree.Removethesebrancheswitharenewal(orbevel)cut(seeFigure6).
2. Removeanyscaffoldbranchorlimbthatishalfthediameterorlargeratitsbasethanthecentraltrunkatthesamepoint(“2‐to‐1Rule”).Abranchofthissizechokesouttheleader,not
allowingthetreetoreachoptimalfruiting.Removesuchbrancheswitharenewalcut.
3. Avoidheadingcuts(oneswhereonlyaportionofthebranchis
removed).Instead,removetheentirelimb. 4. Reducethecomplexityofbranchesintheloweronethirdofthetree.Asbranchesonlateral
limbsgetolder,theydevelopadditionalbranches.Thisiswhatwecallacomplexbranch.Leave
thesmaller,pencil‐thickfruitingshoots.5. Removedownwardhangingbranches.6. Removeshootsthataregrowingstraightup.
7. Leaveoneshootasthecentralleader,anddonotpruneit.
Pruning and Training Peach Trees
Pruningpeachtreesdiffersgreatlyfromthepruningandtrainingofapples.Sincetheyfruiton
Figure5.Limbangleaffectsgrowth,butnaturalgrowthismorevigorousatthetopofthetreethanatthebottom,withthesamebranchangle.
Figure6.Renewalorbevelcutwithincreasethechancesofanewusableshootbeingproduced.
theshootsthatwereproducedinthepreviousseason,itisimportanttoobtaingoodgrowtheachyearforthefollowing
yearsfruiting.Peachtreesareveryvigorousandhavethecapacitytogrowagreatdealeachyear.Becauseofthenatureofthetreeandthewayfruitareproduced,peachesarebest
growntoanopencenter(orvase)form(seeFigure7).Treesshouldhave3to5mainscaffoldbranchesoriginatingfromatrunk,2‐3feetfromthesoilsurface.Thisstructureshouldbe
developedbypruninginthefirstfewseasonsafterplanting.
One‐year‐oldshootsthatarereasonablylongandabout1/4”indiameterproducethebestlargefruit,sothegoalinpruningistomaintainasmanyofthoseaspossible.Awellmanagedtree,however,willproducemorethanenoughoftheseshoots.Amaturepeachtreeneedsonlybetween75and90of
theseshootstoproduceafullcrop.Peachescannotmatureasmanyfruitastheynormallyset,requiringremovalofsignificantnumbersofyoungfruiteachyear.Reducingthenumberofshoots,particularlytheonesoflowerfruitingpotential,candramaticallyreducetheneedtoremoveyoungfruit.Peach
pruningandtrainingrules:
1. Delaypruninguntiljustpriortotheopeningofflowers,onadryday.
2. Removethestrongest,mostuprightshoots
completely,ifpossible.3. Removeshootsthataredroopingsignificantly
belowhorizontal.
4. Oftheshootproducedinthepreviousseason,selectbetween75and90whicharelong,without
sidebranches,andatleastthediameterofapencil.RemoveALLothershoots.SeeFigure8.5. Aftertheflowerhasfallenoffandthedevelopingfruitletisvisable(lateMaytoearlyJune),
removeexcessfruit,leavingnomorethanonefruit
every10inchesalongthelengthoftheseshoots.SeeFigure9.
6. InearlyJuly,removeverystrong,vertically
growing,newshoots.
Peachtreesoftenareshort‐lived,butiftheyareprunedproperlyindryconditionsandthinnedwelleachyear,theyshouldbeabletoproducefruitfor10to15
yearsbeforetheyneedtobereplaced.
Issued by University of Massachusetts Extension, Nancy Garrabrants, Director, in furtherance of the acts of May 8 and June 30, 1914. University of Massachusetts Extension offers equal opportunity in programs and employment. F‐132:1/08‐500
Figure7.Peachtreetrainedtoanopencenter(vase)form.
Figure8.Highqualityshootsonpeachtrees.
Figure9.Thinningpeachfruitletsisrequiredforacropoflarge,high‐qualityfruit.