AustralianNativeTerrestrialOrchidsintheRiverinaregionofNSW

Australiahasapproximately1700speciesoforchids.Ofthenamedspecies,82%areterrestrialsandtheremaining18%areetherepiphytesorlithophytes(5).Theterrestrialsfallwithin115generaandtypicallygrowinsclerophyllopenforestsandswampycoastalscrubandgenerallydonotoverlapwiththeepiphytes.All115terrestrialgeneraarefoundincoastalregionsbut71oftheseextendintolowerrainfallinlandareas(5).Terrestrialsalsocanbefoundfurtherinlandthanmostepiphytesgrowinginareasreceiving500mmorlessrainfallintheRiverinaregionofNSW.ThemapatrightshowsthedistributionoftheFringedSpiderorchidinNSW(11).

ThemajorityofAustralianterrestrialorchidsareadaptedtothehotdrysummersandmoistcoolwinterstypicalofsouthernAustraliaalthoughtheycanbefoundgrowinginthetablelandareasofcentralQueensland.Theirdormancyoversummerandundergroundstorageorgans,(mostlytubers)protectthemfromtheheatanddrynessofsummer(5).Theyreshootinautumnwiththearrivalofcoolermoistconditions.

TheAustralianNationalBotanicGardenwebsite(5)givesadetaileddescriptionofwhereterrestrialorchidsarefoundinAustralia.

Note:Nativeorchidsareprotectedanditisillegaltotakethemoranypartofthemfromthewild.Manyareregardedasendangered.Onlysourceplantsfromreputablegrowers.

MostAustraliannativeterrestrialorchidsaredeciduous,growingfromautumnthroughtospringanddyingbacktoanundergroundtuberoversummer(4).

Australiannativeterrestrialorchidsrelyontheirassociatedmycorrhizatoabsorbnutrients.SomeorchidssuchasGastrodiasesamoides(PotatoOrchid),Dipodiumpunctatum(theSpottedHyacinthorchid),andtwospeciesofRhizanthellalackchlorophyllandrelyonthemycorrhizatoprovideessentialcarbohydrates(8).Theseorchidsarecalledsaprophytic.Terrestrialorchidsneedtheirassociatedfungalmycorrhizaforseedlingstosurviveandoftenthroughouttheirlifecycletoprosper.

Theycanbearrangedinto3groupsdependingonhowtheygrow(9);(1)Colonyformers-thesereproducebyproducingextratuberseachyearandarethebestspeciestostartgrowing(2)Solitary-theseseldomeverproducemorethanasinglereplacementbulbandaremoredifficulttogrow(3)Non-photosynthetic-theseorchidsgettheirnutrientsfromdecayingorganicmatterandmycorrhizaandareimpossibletocultivate.

LesNesbittpreparedthefollowinglistofterrestrialorchidgeneraasbeingsuitableforcultivation(3).

Acianthus Corybas Eriochilus Malaxis Spathoglottis

Caladenia Cryptostylis Geodorum Microtis Spiranthes

Calanthe Cyrtostylis Glossodia (not easy) Phaius Thelymitra

Chiloglottis Diuris Lyperanthus Pterostylis

Ofthese,herecommendsthefollowing10deciduousterrestrialorchidspeciesforgrowinginsouthernAustralia.

• Caladenia menziesii (Spider orchids) • Chiloglottis trapeziformis (Broad-lip bird orchid) • Corybas diemenicus (Helmet orchid) • Cyrtostylis reniformis (Mosquito orchids) • Diuris lanceolata (Donkey orchid) • Eriochilus cucullatus (Bunny Orchids) • Microtis unifolia (Mignonette orchid/common onion orchid) • Lyperanthus suaveolens (Rattle beaks) • Pterostylis curta (Common Nodding Greenhood) • Thelymitra antennifera (Sun orchid)

GlossodamajorWaxlipOrchid

CaladeniatentaculataGreencombor

Fringedspiderorchid

EriochiluscucullatusParson’sBandsorchid

BeginnersarerecommendedtogrowspeciesthatcolonisequicklysuchasPterostyliscurta,P.pendulata,P.nutansandP.truncata(9).Theseareallcolonyformingandmultiplywell.OtherspeciestotryincludeDiuris,Thelymitra,Acanthus,Chiloglotis,Cyrostylis,Spiranthes,CorybasandCorysanthes.ThesedowellintheCanberraenvironment(9)andsoshouldbesuitedtotheRiverinaregion.Canberragrowersreportthatmostcoastalnativeterrestrialorchidsgrowinthehot/coldCanberraenvironmentsoshouldalsogrowintheNSWRiverinaenvironment(9).

Housingandwatering

NativeterrestrialorchidsinsouthernAustraliaarebestgrowninashadehousewith50-70%shade(3)althoughsomegrowersuse90%shadecloth(9).Mostwilltoleratealightfrostdownto-2°C.Theyneedgoodairmovementandmaygetfungaldiseasesiftheairishumidandstagnant(4).

Potsshouldbekeptoffthegroundtodeterpestssuchasslugsandsnails.Theyarebestgrownunderasolidroofinsummertoprotectthemfromsummerrainifthisislikely(4).

Oncefloweringhasfinishedandleavesturnyellow,stopwateringandletthepotdry(9).Tuberswillrotiftheystaywetafterfloweringisfinished(4).

Repottingandpottingmedium

RepotplantsannuallyinDecember-Januarywhentubersaredormant(9).Asuggestedsoilmixis2partscoarsesand,1partrichloam,1partcoarsewoodchips,1partleafmould.Use10-15cmdiaplasticpotswithsufficientholesforgooddrainage(2).Anotherrecommendedmixis45%loam,50%coarsesand,and5%peatmoss(3).Othersusestraightseedraisingmixwithoutaddedfertilizer(9).Drainagemustbeverygood.Asmallamountofbloodandbonecanbeaddedtothemix(4).Typically1dessertspoonofbloodandboneperlitrepottingmix(6).Tubersshouldbeplacedabout30mmbelowthefinalsurfaceandthesurfacecoveredwithafinechoppedmulchofpineneedles.Trytouseequalquantitiesofthenewpottingmixcombinedwithlastyearspottingmixasthisensuresthemycorrhizalfungiistransferredtothenewmix(6).Upto20tuberscanbeplacedina150mmpot.Thefrequencyofrepottingvarieswiththegenus,someneedrepottingeveryyear,otherseveryseveralyears,dependingonhowquicklythemultiply.

Fertilizers

MostAustralianterrestrialorchidsgrowonlowfertilitysoils(5).Asaresultfertilizersarenotnecessarywithsufficientnutrientscomingfromdecomposingsurfacelitterandleafmouldaddedtothepottingmedium.Asmallamountoforganicfertilizersuchasbloodandbonecanbeaddedtothepottingmixwhenrepotting(seeabove)butliquidfertilizersmaykilltheplants(4).PterostylisandDiurisaremorehardyandrespondtoveryweakliquidfertilizer(3,4).MostAustralianterrestrialorchidshavedevelopedonacidsoilsbutafewarefoundonalkalinecalcareoussoils(5).

Mulching

Mulchingofterrestrialorchidsisveryimportant(1).• Itprovidesnutrientstofungiassociatedwiththeorchids• Protectstheorchidsfromdamagingrain• UseafinemulchsuchaschoppedSheoakorRadiatapineneedlesor

smalldiametermulchthatdoesnotsmothertheleaves(3).• Don’tuseamulchthatbecomessoggyasthiscancauseleafrot.• ApplymulchyearlyfromFebruarytoMarch

AcianthuscollinusInlandMosquitoOrchid

ThelymitirasppSunorchid

Pests

Snails,slugsandmealybugsaremajorpests.Mealybugswillgoundergroundandfeedonthetuberwhendormant.Tocontrolthem,whenrepottingsoakthetubersinasystemicinsecticide(9).

CareofnativeterrestrialsthroughtheyearinsouthernAustralia(2).

MostAustralianterrestrialorchidsinsouthernAustraliagrowintheautumn-winterperiodandaredormantoversummerwhichistheoppositetomostexoticandepiphyticorchids.Theircareisthereforeverydifferent.

Summer• Waterdormantplantsverylightlytopreventtubersdesiccating,perhaps

every3weeks.• DivideovercrowdedpotsinlateDecember-January• Addfreshleaflitter

Autumn• StartheavierwateringfrommidMarchanddon’tletpotsdryout,but

theymustnotbetoowet.• LeavesappearfromlateAprilonwardstomidwinter.

Winter• Flowerbudsmaycommenceappearing

Spring• FlowerspresentfromAugusttoOctober• Allowpotstoslowlydryoutandplantstodiedown

PterostylisnutansParrot’sBeakorchidor

NoddingGreenhoodorchid

CaladeniacarneaPinkfingersorchid

PterostylisfalcataSickleGreenhood

GlossodiamajorWaxliporchid

CalochilusplatychilusPurpleBeardOrchid

Photographs

AlltheimagesinthisgrowingguideweretakenoforchidsgrowinglocallyintheRiverinaregionofNSWbyDavidOrchard.Theycanbefoundathiswebsite(7)listedbelow.

DiurispardinaLeopardorchid

CaladeniafuscataDuskyfingerorchid

DiurissppDovetailorchid

ThelymitrapaucifloraSlendersunorchid

CaladeniacaeruleaBluefingersorchid

FieldGuideandonlineresources

PhotographsanddetaileddescriptionsofPterostylis(Greenhoodorchids),Diuris(Donkeyorchids)andCaladeniaspp(SpiderOrchids)canbefoundattheOznativeplantswebsite(10).

Thebook“OrchidSpeciesoftheShoalhaven”byAlanStephensonisahandyfieldguidefullofcolourphotographsthatwillassistinidentifyingmanyofthenativeterrestrialorchidspeciesfoundinsoutheasternNSW.Itisavailablefromaffine@tpg.com.au.

ThePlantNETsiteisanothergoodsourceofinformationshowingthedistributionofbothterrestrialandepiphyticnativeorchidsinNSW(11).SimilarlytheAustralianNationalBotanicGardenwebsite(5)describesthediverserangeoforchidhabitatsacrossAustralia.

Referencesandfurtherreading

Theinformationcitedinthisinformationsheetisdrawnonthereferenceslistedbelow.Pleaserefertothemwherepossibleformoredetailedinformation.

1. NativeOrchidSocietyofSouthAustralia.Orchidblog.http://nossa.org.au/tag/growing-terrestrial-orchids/

2. HowtogrowAustralianNativeTerrestrialOrchids.ANOSVIC.http://www.anosvic.org.au/ANOS_Terrestrial_Cultivation_Notes.pdf

3. AustralianNativeOrchidsbyLesNesbitt.http://anpsa.org.au/APOL19/sep00-1.html4. AustralianNativeTerrestrials.OSONSW.

http://www.orchidsocietynsw.com.au/AustralianNativeTerrestrials.htm5. IntroductiontoAustralianOrchidaceae.https://www.anbg.gov.au/cpbr/cd-keys/orchidkey/html/intro-

c.html6. Nativeterrestrialorchids-givethemagobyFrankieFraser.OSCOV.

http://www.oscov.asn.au/articles5/terrestrials.html7. BirdwatchinginWaggaWagga.https://waggabirds.wordpress.com/category/flora/8. Australianfungi.AustralianNationalHerbarium.https://www.anbg.gov.au/fungi/mycorrhiza.html9. Australianterrestrials.GrowingOrchidsinCoolClimateAustralia(secondedition).EdbyMJFraser,J

Wright,WFerris.OrchidSocietyofCanberra.(2013).10. Oznativeplants.http://www.oznativeplants.com/plant/Greenhood-Orchids.html11. PlantNET.NewSouthwalesFloraOnline.http://plantnet.rbgsyd.nsw.gov.au/cgi-

bin/NSWfl.pl?page=nswfl&lvl=sp&name=Caladenia~tentaculata

Updated2/12/15

Thesenotesareintendedasaguideonlyandarecomposedfromavailableinformationandlocalexperience.TheWaggaWaggaOrchidSocietyanditsmembersarenotresponsibleforanylossordamagetoplantsthatmayoccur.

DiurissulphureaTigerorHornetorchid

DistributionofTigerorchidinNSW