Hydrangeas Demystified Soares Flower Garden Nursery 1021 Sandwich Road East Falmouth, MA 02536 508-548-5288

Identify your hydrangeas.There are six main types of hydrangeas commonly grown in North American gardens.

All hydrangeas have similar cultural needs, requiring:• Moistbutwell-drainedsoil(hydrangeaswillnottoleratewetfeet–ever!)• Somesuneachday.Mostpeoplethinkofhydrangeasasshadeplants,buttheylookandflowerbestwithatleast4hoursofsun,ideallyinthemorning.Paniclehydrangeasarethemostsuntolerant,andcantakefullsuninnorthernclimates.

• Plentyofwater,especiallyastheyaregettingestablished.Hydrangeashaveshallowroots,sotheydryoutquickly.A2-3”thicklayerofshreddedbarkmulchisauseful addition to any hydrangea planting.

Hydrangea Fun FactThereareabout49speciesofhydrangeas.FourspeciesarenativetoNorthAmerica,includingsmoothhydrangeaandoakleafhydrangea.

Climbing Hydrangea petiolaris

HardytoUSDAzone4

Hydrangea Fun FactHydrangeasarenotoriouslywater-needy,butthe “hydra” part of their name actually refers

totheseedcapsules’resemblancetoancientGreekwater-carryingvessels.

Big-leaf (alsoknownasflorist’shydrangea,hortensia,mophead,orlacecap)Hydrangea macrophylla HardytoUSDAzone5ProvenWinners®varieties:

Abracadabra® series, Cityline® series, Edgy® series,Let’sDance® series,

Paraplu™,PinkShira™

Panicle(alsoknownaspeegeehydrangea)

Hydrangea paniculata HardytoUSDAzone3ProvenWinners®varieties:

Bobo®, Fire Light™, ‘Limelight,’ Little Lime™, ‘LittleLamb,’PinkyWinky®,QuickFire®

Mountain Hydrangea serrata

HardytoUSDAzone5ProvenWinners®varieties:Tuff Stuff™, Tiny Tuff Stuff™

Oakleaf Hydrangea quercifolia HardytoUSDAzone5ProvenWinners®varieties:

Gatsby™ series

Smooth (alsoknownasAnnabellehydrangea)

Hydrangea arborescens HardytoUSDAzone3ProvenWinners®varieties:

Incrediball®,Invincibelle® Spirit, WhiteDome®

City

line®RioHydrangea

Bobo®Hydrangea

Incrediball®Hydrangea

Gatsby’sMoon™Hydrangea

Tuff

Stu

ff™Hydrangea

Hyd

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FloweringThetrickiestthingabouthydrangeas is that different typeshavedifferentfloweringhabits:Panicle and smooth hydrangeasfloweronnewwood(growthcreatedinthecurrentseason).Flowerbudsonthesehydrangeasform after the plant leafs out in spring, and open a few months later in summer. As aresult,theseplantsflowerreliablyeachyear,nomatterhow cold the winter was.Big leaf, mountain, oakleaf, and climbing hydrangeas floweronoldwood(growthcreatedinthepreviousseason).Flowerbudsonthesehydrangeasbeginto form in late summer and mustremainundisturbedall through the fall, winter, spring,inordertoflowerthefollowing summer. As a result, theseplantswillnotflowerif:• Theyarepruned.Pruningatanytimewillremovepotentialflowerbuds.

• Theyarebrowsedbydeer,whichwilleattheflowerbuds.

• Theyaredamagedbyweather.Winterweatherisn’tactuallytheproblem;rather, it is in spring, whenseveraldaysofwarmtemperatures are followedbyasuddenfreeze,thatflowerbudsaremostlikelytobedamaged.

Reblooming hydrangeas, alsoknownasremontanthydrangeas,aretypesofbigleaf and mountain hydrangeas thathavetheuniqueabilitytofloweronbotholdandnewwood.Evenifthebudsaredamaged in winter weather, theplantcanstillfloweronwood it produces that season. RebloominghydrangeavarietiesincludetheLet’sDanceseries,andTuffStuff.

It is the ways in which these six hydrangeas differ that make them confusing.

You are always welcome to contactuswithquestions–visit www.provenwinners.com/feedback. We’llgetbacktoyourightaway.

ColorAll hydrangeas undergo some color change as their flowersage,butonlybig-leafand mountain hydrangeas can change their color in a predictable,controllableway.ItisnotthepHofthesoilthatisresponsibleforthischange–itisactuallythepresence of aluminum in the soil that does it. • Certainvarietiesofbig-

leaf hydrangeas cannotexperience color change– generallyspeaking,themore intense the color, the lesslikelyitcanchange(Cityline®Parishydrangeaisagoodexample).Similarly,whitevarietiesofbig-leafhydrangeawillnotchange color.

• Itiseasiertochangeahydrangeafrompinktobluethanfrombluetopink,butbothendeavorsinvolvefrequent,well-timedapplications of aluminumsulfateorthatcanbecometoxic to the plant, so arenot recommended.

• Penniesornailsinthesoilwillnotchangetheflowercolor!

Hydrangea Fun FactBig-leaf hydrangeas and mountain hydrangeas are closelyrelatedandnativetothesameregionofJapan,butmountainhydrangeashavebetterbudhardiness becausetheyoccur in the mountains where conditions are harsher.

Hydrangea Fun FactAhydrangeaflowerconsistsoftwodifferenttypesofflorets:theshowy,paperyflowersareknownassterilefloretsandserveonlytoattractpollinators;thetinyfertilefloretsarewherepollinationandseed-settakeplace.Mopheadhydrangeas are comprised mostly ofsterileflorets;lacecapsmostlyoffertileflorets.

Pruning• Avoidpruningrebloominghydrangeasandthosethatflower

on old wood, altogether. Instead, site these hydrangeasappropriatelysotheydonotneedtobepruned,andchoosevarietiesthatdonotgettoobigfortheirspace.

• New-woodfloweringhydrangeascanbeprunedeachearlyspring,justasthenewgrowthbeginstoemerge.Removeuptoone-thirdoftheheighteachyearifdesiredtoencouragevigorousnewgrowthandstrongstemstosupporttheflowers.

• Hydrangeasdonotstrictlyrequireregularpruning.Theywillgrowandflowerwellwithnothingmorethanremovalofspentflowersandanydeadwoodeachearlyspring.