Gardening Australia – September 2019

PLANTS

T

reefernsareamongtheworld’s

mostancientplants,having

survivedQueensland’sown

Jurassicdinosaur,Rhoetosaurus

brownei,nibblingtheirfrondsabout

165 millionyearsago.Awe-inspiringin

thewild,theyadddramaandrainforest

appealwhenplantedinthegarden.Used

strategically,treefernscanbecomethe

starsoftheshowinthelargestgarden

orthetiniestcourtyard.Theirspectacular

sculpturalhabitissetoffbylow-growing

plantsthathavesimilarcarerequirements.

Gettingstarted

TreefernsgrowmostlyintheSouthern

Hemisphereandareoftenassociatedwith

thetropics.InAustralia,theyalsogrow

naturallyinsubtropicalandtemperate

rainforests,aswellasmoist,openbushland

andferngullies.Theydowellinlightto

heavyshade,althoughmostwillcope

withearly-morningsun.Manyofushave

shady,underusedspotsinthegarden,

oftenonthesouthsideoftheproperty,

andtheseareasareperfectforletting

yourinnerpteridomaniacgowild!

Thebesttimetoplanttreefernsis

autumn,latewinterandspring.Choose

apositionoutofstrongwind.They’re

adaptabletodifferentsoiltypes,aslong

asitholdsmoistureandhasaneutral

toslightlyacidicpH.Addorganicmatterto

theplantingholetohelpretainmoisture.

Plantpottedspecimenstothesamedepth

astheyareinthepot.Ifgrowingthem

fromatrunk(seeDicksoniaspecies,below),

plantthemdeepenoughsotheyarestable.

Watertheplantinwell,andensureit

neverdriesoutforthefirst 12 months.After

that,wateronceaweek,asneeded,during

drytimesfromspringtoautumn,applying

watertothetrunk,too,butnotthecrown.

Maintainagoodcoveroforganicmulchto

keepthesoilmoist.Feedwithwell-rotted

animalmanuresorcommercialorganic

fertilisersinautumnandspring.

Dicksoniaspecies

Althoughit’soneoftheslowest-growing

species(2.5cmperyear),thesofttree

fern(Dicksoniaantarctica)isarguably

themostcommonlygrownbecauseof

itsresilienceonceestablished.Itcanbe

purchasedinapotorasasawntrunk

(withorwithoutfronds).It’soneofthe

fewtreefernsworldwidethatgrowsnew

rootsfromthebaseofacut-offtrunk,but

thepartleftinthegroundwillnotreshoot.

Plantingasemi-maturetrunkcreates

instantvisualimpactinthegarden.With

a50cmdiameter,it’soneofthewidest

Prehistorictreefernshaveitmadeintheshade,adding

megadramaanda‘lostworld’feeltothegarden,writes ABBISHOP

PHOTO

GAP PHOTOS/NOVA PHOTO GRAPHIK

GARDENINGAUSTRALIA SEPTEMBER 2019 25

Ju ic

OPPOSITE

Underplanted with spider lilies,

this lacy tree fern (Cyathea cooperi)

thrives in the shade cast by palms.

at a glance

common name

tree fern

botanic name

Dicksonia spp., Cyathea spp.

planttype

trunk-forming ferns

4–20m

2–6m

sun, semi-shade,

shade

autumn, late winter,

spring

suitable