pruning and training fruit trees in the home landscape · pruning and training fruit trees ......

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Pruning and Training Fruit Trees in the Home Landscape Wesley R. Autio 1 , Winfred P. Cowgill, Jr. 2 , and Jon M. Clements 1 1 University of Massachusetts and 2 Rutgers University Deciduous fruit trees have long been a part of the home landscape. The grace of the tree and beauty of the bloom make them very attractive plants, but the taste of fresh fruit from a well managed fruit tree is unsurpassed. Unfortunately, however, fruit trees provide several horticultural challenges, a significant one being tree training. We use “training” rather than or in addition to “pruning” to reflect the wide variety of techniques that should be used to manage both the vegetative (shoots and leaves) and the reproductive (flowers and fruit) growth of the tree. Because of the brevity of this publication, we will concentrate on two species of tree fruit, apples and peaches. They, generally, typify two categories: trees which flower and fruit largely on spurs originating on 2‐year or older wood (apples, pears, plums, apricots, and cherries) and trees which flower and fruit on 1‐year‐old wood (that which was produced last year) only (peaches). General Considerations Why prune and train? A desirable fruit tree in the landscape is one which produces high quality fruit annually, is structurally sound, and is aesthetically pleasing. Pruning and training are used to enhance light penetration into the tree canopy and as a result cause the tree to produce large and tasty fruit throughout. Pruning and training are used to increase branch strength and eliminate weak branches so that the resulting canopy is capable of carrying a fruit crop without limb breakage. Both pruning and training also are used to maintain the tree canopy in the available space and to make that the most visually pleasing tree possible. Be aware that there may sometimes be a conflict between optimal fruit production and aesthetics. Tools. Pruning of fruit trees requires three primary tools (see Figure 1). Bypass hand pruners are a necessity. Good quality pruners, such as Felco or Pica, should cost between $35 and $60. You also should have a pair of bypass loppers (24‐26”) with a nicely curved hook on the blade. Barnell, Corona, and Bahco produce loppers in this category cost between $45 and $100. The last tool is a good saw. Our favorite is a 13” curved blade pruning saw with a Japanese‐style blade (Tri‐cut, Tiger Tooth, Turbo Cut, etc.). This is a pull saw with a very sharp blade and costs between $20 and $30. It is best also to purchase a sheath or scabbard for the saw to both protect the blade and you from the blade ($20 to $30). Season of pruning. Pruning is best done on dry days in the late winter or early spring. Apples, Figure 1. Basic tree‐fruit pruning tools.

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Page 1: Pruning and Training Fruit Trees in the Home Landscape · Pruning and Training Fruit Trees ... Pruning peach trees differs greatly from the pruning and training of apples. Since they

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.

Page 2: Pruning and Training Fruit Trees in the Home Landscape · Pruning and Training Fruit Trees ... Pruning peach trees differs greatly from the pruning and training of apples. Since they

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.

Page 3: Pruning and Training Fruit Trees in the Home Landscape · Pruning and Training Fruit Trees ... Pruning peach trees differs greatly from the pruning and training of apples. Since they

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.

Page 4: Pruning and Training Fruit Trees in the Home Landscape · Pruning and Training Fruit Trees ... Pruning peach trees differs greatly from the pruning and training of apples. Since they

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.