HAWAII AGRICULTURALEXPERIMENT STATIONUNIVERSITY OF HAWAIIRESEARCH BULLETIN 147APRIL 1970

CONTENTSPage

. Proteas: What They Are 5Descriptions of Selected Proteas -________________________________ 8Proteas Suggested for Landscape U se ---------- 12Proteas Suggested for Cut Flowers ~__________________________________________________________16Propagation of Proteas 17

Seedage _____________________________________________________ ______________________________________ _______________________ 17Cuttings 17G r aft ing .. .____________________________________________________________________________________ 18

Cultivation of Proteas 19Soil 19

Planting ._______________ ___ 19Pruning __________________________________________________________________________________________________________________ 20

l\I.[ar}(eting 2()J:)emGlIld 2()

Price -_. _ 21Economics of Production - -_ 21Potential Outlets - _ __ _ 22

Sources of Seeds and Plants 22References _____ ___ ____ ___ __ _ ___ ___ ___ __ ____ ____ _ _ _ __ _ __ __ __ _ __ __ 23

Proteas under Evaluation at Kula 24

PLANT NAMESAll scientific plant names are based upon the 1969/1970 Index Seminum of

the National Botanic Gardens of South Africa. Synonyms are those currentlybeing used commercially. Readers working with older plant listings may findselected former species names for proteas on the back cover of this publication.

THE AUTHORSDonald P. Watson is Specialist in Horticulture, Hawaii Cooperative Exten­

sion Service,and Professor of Horticulture, College of Tropical Agriculture,University of Hawaii. Philip E. Parvin is Associate Horticulturist and Superin­tendent, l\I.[aui Branch Station, Hawaii Agricultural Experiment Station, Kula,l\I.[aui.

PHOTO CREDITGrateful acknowledgment is made to South African Airways for the color

photography which they have contributed to this publication.

CULTURE OF ORNAMENTALPROTEAS

by

DONALD P. WATSON

and

PHILIP E. PARVIN

This project was made possible bythe McInerny Foundation in Honolulu.

SOUTH AFRICAN AIRWAYS

King protea (Protea

4

cynaroides) .

CULTURE OF ORNAMENTAL PROTEAS

Donald P. Watson and Philip E. Parvin

Proteas: What They Are"Protea" refers to any member of

the family' Proteaceae, which includesover 1500 species of trees, shrubs andherbs from the southern hemisphere,especially Australia and South Africa.All members of South A f ric a nProteaceae are woody evergreens,usually with entire, leathery, and oftenhairy leaves; and are not indigenous toany other parts of the world.

Proteas are outstanding because. oftheir style of -growth and the architec­tural quality of their flowers.

Typifying the great variation foundamong the genera in this family, theterm "protea" was derived from thesea-god Proteus who could readilychange into any form he chose. Thesmall individual flowers of the largemacadamia tree, the huge flowers ofthe king protea, or the yellow-, red-, oramber-colored flowers of the ground­hugging, creeping pincushion provide

5

evidence of the great variation withinthe family.

Silky oak (Grevillea robusta) or"oka-kilika," used widely in the Islandsfor reforestation; macadamia (Macada­mia integrifolia) , introduced in 1890and planted for its edible nuts; fire­wheel tree (Stenocarpus sinuatus) ,with scarlet, wheel-like flowers, rarelyseen but a spectacular ornamental; andkahiliflower (G revillea banksii) or"ha'iku" are some members of thefamily that have been grown in Ha­wall.

The genus Protea is characterized bylarge bracts, often brightly colored, sur­rounding a composite flower. Thesebracts may be smooth or pubescent(covered with velvety hair). Some spe-cies have bracts tipped with dark "fur"and are called "bearded." The pre­dominate color in this genus is pinkwith occasional albinos. Other colorsare reds and more rarely greens.

Protea, the national flower of SO~_lthAfrica, refers especially to Proteacynaroides, the giant or king proteawhich has flowers up to 1 foot in dia­meter.

Protea repens, sugarbush, with itsrosy-tipped, sticky bracts forming anurn, Leucospermum cordifolium, nod­ding pincushion, with pink, yellow ororange dome-shaped flowers, and Leu­cadendron argenteum, silver tree, withits glistening, grayish-blue foliage, areother popular proteas from Africa.

Potential for Hawaii

Many years ago, few people wouldhave thought that Hawaii-grown mac­adamia nuts would whet the appetiteof gourmets all around the world. Mac­adamia, however, is but one highlyesteemed member of the family Protea­ceae. Flowering proteas are so greatlyadmired in South Africa that they areused as emblems on the coins andstamps. In Australia the waratah(Telopea speciosissima) , a magnificentcrimson peony-like bloom, is the stateflower of New South Wales.

Through the dissemination of seedand information, the National BotanicGardens of South Africa, at Kirsten­bosch, has been largely instrumental inbringing into cultivation the ornamen­tal menlbers of Proteaceae.

While the ornamental members ofthe family have been somewhat neg­lected even in their native habitat untilrecently, ten years ago, Marie Vogts,president of the South African Associa­tion for the Advancement of Science,observed that there were astounding

6

possibilities of economic importancefor these plants. She stated:

"The fact that the South AfricanProteaceae have lately been grownunder a variety of conditions hasonce again focused the eyes ofthe world on them. Already ananxious competition to be first inthe world market has set in. I anlnot only judging from reports inthe Press and froln enquiries madethrough the various embassies but

also from numerous letters re­ceived in recent months fromplaces as far apart as Hongkong,Chicago, Towoomba, Dresden andNairobi, not to nlention places inregions such as Western Australia,New Zealand, California andSouthern Europe, where one wouldexpect interest because of a simi­larity in clhnate. It would appearthat there is again a great demandfor new and uncomInon gardenplants. Proteas are outstandinglyeffective both as garden shrubsand as cutblooms. They flower forlong periods, often for more thanhalf -~ year and the flowers carryand last well."

SOlne proteas for landscape usageare being grown comnlercially in SouthAfrica, Australia, New Zealand, a fewnear Nice in the South of France, inCorsica, the Scilly Isles and Cornwallin England. Some are also being pro­duced in Florida and California.

A limited number of small growersin Australia and New Zealand producecut flowers from nursery-grown plants.These are marketed locally at relative-

Nodding pincushion (Leucospermum cordifolium) growing at Kula, MauL

ly low prices and a few are exportedfor special exhibits and special orders.I t is not unusual to see passengers car­rying boxes of proteas in the air ter­minals in South Africa. Many of thecut flowers are gathered from nativeplantings. Lack of uniformity, consis­tent supply, and good quality reducethe export market for South Africa.Protea export is further limited byplant inspection and high airfreightrates to markets in Europe, Japan, andNorth America.

I t is estimated that there will bemore than 20 acres of proteas in pro­duction for cut flowers in California bythe early 1970's. This acreage will belimited to three or four species, andthere have already been instances offrost damage In locations alreadyplanted. Sales are reported brisk anddemand is good whenever these flowersbecome available in the market. In a

7

very few special locations in Florida,proteas are also being tried.

As with the macadamia, however,there are locations in Hawaii, especial­ly above 2000 feet elevation, ideallysimilar in soil and climatic conditionsto those where proteas grow in theirnative habitat. Based on tests to date, itis apparent that Hawaii-grown proteascould rival those produced anywhereelse in the world. Due to their exoticappeal and excellent shipping andkeeping qualities, further research anddevelopment of cultural and crop man­agement practices is underway.

Proteas are not exactly easy plants tomanage. Their growth response is un­predictable. They grow naturally inwell-drained acid soils of granite originon hillsides. Some are productive insandy soils, others in deep, rich soil;but all of them apparently thrivewhere there is plenty of cool fresh

breeze. They cannot tolerate close hu­mid conditions or poor drainage andoverwatering., In 1965, Dr. David Williams intro­

duced 50 species of proteas and be­gan evaluating them at Kula, the MauiBranch of the Hawaii Agricultural Ex­periment Station. Since that time, thepace of this research has been in­creased.

The present research program at theMaui Branch Station is evaluating andscreening as many of the ornamentalproteas as possible, selecting those that

have potential for landscape plants andfor cut flower production. Experimentsare being conducted to determine theshelf life of the crop and the bestmeans of propagation, pruning, fer­tilizing and harvesting.

This publication is intended to sup­ply prospective growers with informa­tion presently available. It must belooked upon, however, as a source ofpreliminary direction which may needsome modification as the experimentsprogress and as more specific data be­come available.

DESCRIPTIONS OF SELECTED PROTEASFrom 1500 species, the following 23

have been selected for description.These include the most successful spe­cies currently being grown in Hawaii,as well as the most promising fromother areas.

Honeycone (Banksia collinia)Bears showy cylindrical heads of

deep honey-colored flowers with pur­plish-brown, protruding s tam ens;leaves are narrow toothed, dark greenwith silvery undersides, borne on slen­der grayish branches; grows to 10 feetas a dense shrub.

Heatherleaf (Banksia ericifolia)One of the most popular banksias;

erect flower cones to 8 inches in lengthmay appear from pale yellow, throughthe more commonly found golden am­ber shades, to a deep orange brown;flowers last 2 weeks in water.

Leaves are narrow, needle-like, Y2inch long, deep green with silvery re­verse, densely covering a bush from 6to 10 feet in height.

8

Cutleaf (Banksia grandis)The largest of the banksias, reaching

40 feet in height with 12-inch leaves,cut to the midrib in triangular seg­ments, yellowish green above and sil­very below; the large cones of yellow­ish-green flowers are 12 inches longand .conspicuously placed.

Shooting star (Banksia occidentalis)Cylindrical heads of bright brown­

ish-red flowers, 4 to 6 inches long;borne on ends of ascending reddishbranches; leaves narrow, 6 inches long,shiny above, with velvety texture be­neath, forming a neat-growing shrubto 8 feet tall.

Goldcone (Banksia spinulosa)Bears elongated cones of deep-yellow

to reddish-orange flowers; leaves nar­row, dull green; and the plant resemblesa compact form of B. ericifolia, growsonly 4 to 6 feet tall.

Silver tree (Leucadendron argenteum)The silver foliage of this tree in the

bright sunlight is difficult to describe,

Combflower (Leucospermum catherinae) . Rose-spoon protea (Protea eximia).

Bauer banksii (Banksia baueri).

more conspicuous than the small, yel­low, male pollen-bearing flowers or thesmall, silvery, female cones; flowersappear on separate plants and are notalways present.

The plant, with upright branches, isprized primarily for its foliage which iscovered with leaves overlayed with sil­very hairs that reflect light.

Combflower (Leucospermum catheri­nae)

Yellow, pin-wheel-shaped flowers ona plant 6 feet in height and 6 feet indiameter, with gray-green foliage;flowers freely on the tips of thebranches.

It appears to grow better under cul­tivation, is cold resistant, and does notthrive in hot, dry exposures.

Cripplewood (Leucospermum conocar­podendron)

Conical yellow inflorescence is simi­1ar to some chrysanthemums; in theearly stages the flower is somewhatburied by large, dark-green leaveswhich later open to expose flowers 3inches in vvidtho

Plant gro\vs to a height of 10 feetwith decidp'~ljy tree-like branching

habit. '--l ne gnarled nature of thebranches gives it the name of "crip­plewood" or "kreupclhaut".

Nodding pincushion (Leucospermumcordifolium)

I ts attractive dome-shaped inflores­cence of rosy-orange styles is borne ona sturdy stem with large dark-greenleaves. The flower color varies fromorange yellow to darker rosy orangeand the cut flowers, often 4 inches indiameter, last for 3 to 4 weeks.

10

The plant grows to 6 feet in heightand spreads out to 6 feet in diameter.Being a prolific bloomer, it is coveredwith flowers for 3 to 4 months, oftenyielding more than 100 flowers perplant.

Twin flame (Leucospermum cune~­

forme)Twin flowers about 2 inches in

length open as light-orange pincushionsand as they mature turn darker in col­or; long, dark-green, leathery leavesare deeply notched across the tip andclosely cover the stem.

The plant is a most attractive broadshrub because of the changing color ofits large crop of showy flowers; growsto a height of about 5 feet.Tangerine pincushion ( Leucospermulnlineare)

Derives its name from the color andform of its flower; a somewhat flat­tened pincushion that is borne on long,straight stems with foliage that resem­bles short pine needles.

Plant grows to a height of 3 feet andis especially attractive because of itsneedle-like dark foliage that points up­ward throughout the length of thestem.Ribbon pincushion (Leucospermummuirii)

The name "ribbon" is descriptive ofthe curled, yellow flower with red stripin the center of the inflorescence. Yel­low orange in their overall color andabout 2 inches in diameter, these flow­ers are conspicuously extended beyondthe gray-green leaves.

The plant reaches a height of 4 to 5feet but the overall effect is dainty andless sturdy than some other species.

Tangerine pincushion (Leucospermum lineare).

Creeping pincushion (Leucospermumprostratum)

The small, yellow flowers that areless than 2 inches in diameter darkento red as they mature. Consequently,yellow-, red- and amber-colored flow­ers are present at the same time andconspicuous against the gray-greenfoliage. This plant is a good groundcover for well-drained soil in full sun­light.

Pineleaf (Protea aristata)The brown-colored bud opens into a

deep pink cone-shaped flowerhead thatis borne on the tips of gracefulbranches that are covered with leavesresembling pine needles. By many, thisdeep-pink flower is thought to be oneof the most attractive of the protease

It is a slow-growing plant that is alsoattractive because of the soft, green,needle-like foliage.

11

Grafted specimens seem to displaygreater vigor than seedling plants.

Wooly beard (Protea barbigera)Inflorescence is up to 8 inches in diam­

eter with soft-pink to deep-rose color­ing; cone-like fuzz in the center of theinflorescence rises to a dark-brown orblack peak. Island-grown flowers havenot displayed good opening quality.

The plant grows to 4 feet in heightspreading to 6 feet.

King protea (Protea cynaroides)The flowers often reach 12 inches in

diameter. Pink to crimson bracts sur­round a silver-gray mound of individ­ual flowers. Its resemblance to anartichoke suggests its name "cynara"(artichoke). The plant apparently re­sponds well to heavy pruning and ex-hibits great variation in flower colorwith some forms pale pink and othersdeep red.

PROTEAS SUGGESTED FOR LANDSCAPE USE

Heatherleaf BanksiaBanksia ericifolia

Oakleaf BanksiaBanksia robur

GoldconeBanksia spinulosa

Feathery redGrevillea thelemanniana

KahiliflowerGrevillea banksii

Formosan conebushIsopogon formosus

SuntipsLeucadendron adscendens

Silver treeLeucadendron argenteu.m

Twinleaf BushLeucadendron comosum

Successfully grownFlame Goldtips

Leucadendron eucalyptifoliumBrownring Goldtip

Leucadendron stokoeiGoldtips

Leucadendron xanthoconusCombflower

Leucospermum catherinaeCripplewood

Leucospermum conocarpodendronNodding pincushion

Leucospermum cordifoliumTwin flame pincushion

Leucospermum 'cuneiformeRibbon pincushion

Leucospermum muiriiRocket pincushion

Leucospermum reflexum

King proteaProtea cynaroides

Rose-spoon proteaProtea eximia

Princess proteaProtea grandiceps

Baby proteaProtea lacticolor hybrid

Long-bud proteaProtea longiflora

Bredasdorp sugarbushProtea obtusifolia

Gleaming proteaProtea pulchera

SugarbushProtea repens

Promising but not proven

Banksia baueriBanksia grandisBanksia occidentalisLeucadendron gandogeriLeucospermum lineareLeucospermum tottumProtea amplexicaulisProtea laurifoliaProtea minorProtea nerifoliaTelope~ speciosissima

. Pink mink (Protea nerifolia) in South Africa.

Apparently unsuccessful

Leucadendron daphnoidesUnattractive, brown flowers.

Leucadendron laureolumPoor growth; brown cones.

Leucadendron tinctumPoor growth; brown cones.

Leucospermum bolusiiDirty-white flowers.

Paranomous reflexusOpen, sprawly growth.

A ulax cneorifoliaInsignificant flowers, thin, opengrowth.

Hakea' laurianaWeak~. open growth.

Isopogon petiolarisStunted, slow growth; unattrac­tive flowers.

Isopogon dawsoniiUnsightly flowers.

12

Cripplewood (Leucosperm.um conocarpodendron) at Kula, Maui.

Nodding pincushion (Leucospermum cordifolium) and silver tree (Leucadendron argenteum)in their native habitat.

13

Rarely does the plant grow to morethan 5 feet in height, but its character­istic leaves, with an oval or pointedblade, often grow up to 3 inches across.Red margins on some leaves and char­treuse margins on others make this foli­age most characteristic.

Rose-spoon protea (Protea eximia)One of the most reliable, large-flow­

ered species, with a rich"red center, butwith much variation in the intensity ofthe color of the flowers. Bracts arespoon shaped; flowers reach a diameterof 5 inches and are characterized bythe spoon-like bracts protruding out­ward and upward.

The silver-green leaves are broadlyoval a..nd wrapp"ed thickly around up­righ t branches.

The plant grows 6 to 8 feet inheight, is dense in appearance, andflowers profusely.

Princess protea (Protea grandiceps)

This pale-pink to salmon-pink andred inflorescence somewhat resemblesa single peony; bracts are edged with afringe of silky reddish-brown andwhite hairs that surround arched whiteor yellow pistils. The inflorescence isoften 4 inches in diameter and 6 inchesin length.

The plant grows into a good form 5feet in height. The foliage closely sur­rounds the inflorescence and is a whorlof oval grayish-green leaves with red orbrown margins.

Pink mink (Protea nerifolia)

The name aptly describes the beardof black or purplish, fur, tipping thetopmost bracts of pink. Several colorsare found, from a deep rose pink tolight salmon, and this species is notedfor its profuse blooming habit.

Long-leaved protea (Protea longi/olia).

The plant grows to 10 feet in heightand spreads to 6 feet, with "oleander­like" leaves covered with silvery hairsgiving a velvety texture.

Sugarbush (Protea repens)The unopened bud of this flower is

long, pointed and honey gold at the tipwith the points of the bracts a translu­cent rosy pink. These flower buds, 5inches in length, are attractive beforethey open.

The plant is large and well-shaped,growing to 9 feet in height and 6 feetin diameter. Distinctive long, strap­shaped gray-green leaves complete thepicture of an attractive shrub.

Prince (Protea speciosa)A long, narrow flower bud formed

from layers of creamy yellow to brightpink with distinctive brown tufts onthe tip.

I ts wide, green leaves, 4Y2 incheslong and 2 inches wide with a gray­green color and leathery texture, clingto the stem and often hide part of theflower. It makes a vigorous shrub butrarely grows more than 3 feet inheight.

Blushing bride (Serruria florida)The dainty, creamy-white flowers,

often with a pink and pale-green tinge,are as attractive in bud as when fullyopen. Several flowers on one stem areideal for flower arrangement.

Finely divided, fern-like leaves makesoft and attractive background for theflower cluster. The shrub itself barelygrows to more than 4 feet in heightand is somewhat open and ungainly inappearance. With proper pruning,

15

however, it can be shaped and used ef­fectively for landscape purposes.

Waratah (Telopea speciosissima)The state flower of New South

Wales is a most spectacular deep-redinflorescence 6 to 8 inches in diameterwith the typical incurving habit of thepincushion leucospermum. Leatherybracts of the same color surround theflower and as it opens make ita spec­tacular flowering shrub.

The tree itself, under best conditions,will grow to be 20 feet in height. It re­sponds well to heavy pruning andheavy feeding and makes a good spec­imen plant.

Princess protea (Protea grandicepsJ.

PROTEAS SUGGESTED FOR CUT FLOWERS

Successfully grownCombflower

Leucospermum catherinaeCripplewood

Leucospermum conocarpodendronNodding pincushion

Leucospermum cordifaliumRocket pincushion

Leucospermum reflexumWooly beard

Protea barbigeraProtea pink

Protea compactaKing protea

Protea cynaroidesRose-spoon protea

Protea eximiaBaby protea

Protea lacticolor hybridGleaming protea

Protea pulchra

Rose-spoon protea (Protea eximia).

SugarbushProtea repens

Blushing brideSerruria florida

WaratahTelopea speciosissima

Banksia attenuataBanksia coccineaBanksia colliniaBanksia ericifoliaBanksia grandisBanksia mediaBanksia roburBanksia speciosaBanksia spinulosaBanksia victorialLeucospermum eUipticum

Promising but not proven

Leucospermum lineareLeucospermum vestitumProtea aristataProtea grandicepsProtea harmeriProtea lacticolor hybridProtea laurifoliaProtea minorProtea nerifoliaProtea speciosaProtea stokoei

Apparendy unsatisfactoryLeucadendron species Leucospermum bolusii

Although cones keep well for dried Small, tight clusters of rather un-arrangements, most cones lack the attractive dirty-white flowers.sales appeal of a good cut flower. Protea longiflora

Poor keeping quality-hairs coI­lapse in center of flower.

16

PROPAGATION OF PROTEAS

SeedageIn their native habitat, seeds germi­

nate readily in the soil where they fallfrom the mother plant. Freshly har­vested seed has a higher germinationpercentage than seed that has beenstored for several months.

Controlled self-pollination has re­vealed self-incompatibility in proteaand some leucospermums, but self­compatibility in other leucospermumsand Serruria florida has been ob­served. I t has been assumed by inves­tigators in Africa that the apparentpoor germination often may be attrib­uted to the lack of an effective meth­od of sorting out sound seeds.

"Immature" seed may be collectedas early as 4 to 5 months after flower­ing, but should be planted at once asthis "soft" seed may lose its viabilityrapidly.

Usually, fully ripened seed is har­vested from old flower heads about thetime the next crop of flowers appears.This seed holds its viability for 3 years.

Trials at Kula have indicated thatmature seed of many species willgerminate more rapidly and with ahigher percentage of germination if ithas been soaked in concentrated sulfu­ric acid for 5 minutes before beingthoroughly washed and sown in a well­drained soil mixture. Of the 18 speciestested, only P. longijlora and P. lepido­carpodendron showed higher percentgermination when untreated.

Best results have been obtained bysowing seed in the fall of the year, ascooler weather approaches. At higher

17

elevations, spring planting is also effec­tive.

Sow seeds in a mixture of one-thirdsand, one-third peat or other organicmatter, and one-third vermiculite witha trace of iron chelate. Place fine gra­vel in the lower third of individualcontainers. Treat the seed with damp­ing-off fungicide and place it onthe surface of a well-firmed soil mix­ture, covering it with a layer of perliteor vermiculite.

It is important to locate seed beds inthe open in the full sun where there isgood air movement. Never allow theseed beds to dry out during germina­tion, but avoid hot, close, humid condi­tions. To decrease water loss and in­sure a constant and even supply ofmoisture around the seed, light shadingof the seed bed is suggested until a fewweeks after germination.

Germination varies according to thegenera and the species, but anythingfrom 3 weeks to 3 months and more istypical.

P. barbigera germinated in 10 days,P. eximia started in 19 days, P. cyna­roides in 22 days, and L. cordifoliumin 28 days.

While much emphasis in the past hasbeen placed on the possible presence ofan inhibiting factor reducing germina­tion and regular watering in such away that this factor is washed throughand leached out of the soil, it nowseems to be a discredited hypothesis.

CuttingsSince there is considerable variation

especially in flower color and habit of

growth among plants of the generaLeucospermum, Leucadendron andProtea, vegetative propagation of themost desirable seedlings becomes essen­tial for the production of a uniformcommercial planting.

Cuttings may be rooted in amisthouse \vhere a maximum of sun­light is available and where the mois­ture is reduced during periods of lowor no sunlight. Good air circulation isessential at all times. The leaves are re­moved from the bottom half of the in­dividual cutting.

While the size of cuttings will varyamong the species, 6- to 8-inch termi­nal sections of new growth as soon as itbecomes brittle seem to be the mostsatisfactory material for good rooting.Use of rooting powders before stickingthe cuttings into a mixture of 1 partcoarse soil, 1 part peat, and 1 part cin­ders is recommended.

King protea (Protea cynaroides) rooted cutting.

Nodding pincushion (Leucospermunt cordi/olium')rooted cutting.

Two to three months are requiredfor rooting after which cuttings can bepotted individually in plastic sleeves orother containers where they can beheld under mist in the open air untilthey are well rooted and ready fortransplanting into the field. Experi­m-ental work in New Zealand andSouth Africa indicates that most orna­mental proteas can be propagated bycuttings and that it takes about 6months to produce a plant that isready to be marketed.

GraftingIn Stellenbosch, South Africa, con­

siderable increase in the rate of growthof plants has been obtained by graftingP. aristata on P. compacta, and P.grandiceps on P. compacta. Using awhip and tongue graft of woody stemsabout ~ to 12 inch in diameter gavesatisfactory results.

CULTIVATION OF PROTEAS

Soil

Most proteas thrive In a well­drained, acid soil. A pH of 5.5 to 6.5is ideal and they do best in windy 10­cations or where there is excellent airdrainage. Still, humid air with plantsrooted in a poorly drained, heavy soilis a lethal combination.

Planting

Planting holes should be at least 2feet in diameter and 2 feet deep.

Prepare the planting site well. Re­move the first 12 inches of soil, breakup the bottom layer in the hole, and in­corporate some organic matter. Thehole should then be filled with theoriginal top soil enriched with organIcfertilizer.

In some parts of the world, nurseryplants are produced in plastic sleevesand allowed to become 8 to 12 inchesIn height before they are transplanted

to their permanent location. Nurseryfield-grown plants are usually rootpruned a month or two before diggingfor transplanting. After transplanting,growth is often slow. New, fine rootsare extremely sensitive and may re­spond to the presence of mycorrhiza inthe soil.

Planting distances will vary accord­ing to the species and the pruning prac­tices. Usually planting on 5.:. to 6-footcenters is satisfactory. An averagelength of time from seed to the produc­tion of the first flowers is from 2 to 3years.Th~ sudden death of a plant at any

age is common and most prevalent atthe end of a dry season or after over­watering. A belief that proteas are dif­ficult to cultivate seems to have existedfor some time. Some scientists havesaid that there are toxins in the seedsor in the root system, a naturally pro­duced poison that may inhibit ger-

Protea nursery at the National Botanic Gardens, Kirstenbosch, South Africa.

mination or suddenly kill a large spec­imen. It is likely that this theory is notwell founded and that the suddendeath of a formerly healthy plant canbe attributed to a serious outbreak ofsoil-borne fungi, especially in poorlydrained soil.

While no experimental data is avail­able on the fertilizer requirements, ob­servations indicate that proteas re­spond to a standard fertilizer program.Thorough watering weekly and the useof mulches to conserve moisture is rec­ommended as long as the plants are be­ing grown in a well-drained location.In Southern California, applications ofcottonseed meal around the base of theplant are deemed beneficial.

Pruning

Proteas as a group do not fit into thegenerally accepted idea of a garden

shrub. With a few exceptions, they donot produce quantities of blooms atone time, and many plants are inclinedto become leggy and misshapen withage. The old blooms dry up and persistwith a certain amount of drying anddiscoloration of the foliage during thesummer, making many of the plantsmore suitable for an informal planting.

All proteas must be pruned to pro­duce vigorous growth. All youngplants, with the exception of silvertree, should have their leading tipspinched out when they are transplant­ed. Regular pruning must start whenthe plant is small and be continued asan annual routine. Heavy pruningprevents leggy shrubs and thus willyield larger numbers of better qualityflowers.

For commercial flower production,plants should be disbudded to a singleflower per stem.

MARKETING

DemandProteas are among the longest last­

ing cut flowers. l~hey also dry well,lasting indefinitely in dried arrange­ments. In preliminary tests in Honolu­lu, pincushions lasted 12 days in wa­ter, and 27 days in a preservative solu­tion. Keeping quality studies showedsimilar results in excess of 3 weeks inpreservative solutions for P. barbigera,P. compacta and P. cynaroides.

Proteas also ship well over long dis­tances. Shipments from the West Coastto key cities over the United Stateshave arrived in excellent condition.

20

One of the major obstacles to thesuccessful introduction of a new cutflower is generating a demand for theproduct. Traditionally, the majority ofthe wholesale florists in the UnitedStates stock only what the retail floristdemands, and are understandably waryabout investing in unknown materials.

The best way to acquaint the retailflorist with a new product is throughhis trade press, and through the ever­popular floral desi~n schools held aspart of regional, state and national con­ventions.

Since the first proteas in the U nited

States were grown commercially inCalifornia over 6 years ago, there havebeen several attempts to introducethese flowers to the retail florists. Pro­teas have been featured at florists' con­ventions for several years. In 1968,the Southern California Floral Associa­tion sponsored a floral designer whotraveled the summer design school cir­cuit, using and publicizing protease Inall cases, retail florists are reportedlyimpressed by the "architectural quali­ty" of the flowers and the textures andcolors, but insist upon longer stemlength.

PriceRetailers on the West Coast of the

United States pay from 25 to 50 centsper stem for pincushions, dependingupon stem length and quality. Mid­western and Eastern florists pay up todouble that price when shipping costsand commissions are included.

A second category of proteas, includ­ing pink mink (P. nerifolia) , rose­spoon protea (P. eximia) and sugar­bush (P. repens), averages approxi­mately 60 to 75 cents per flower,F.G.B. West Coast. Due to the scarcityand limited demand for the king pro­tea, retailers on the West Coast pay asmuch as $3 per bloom for P. cynaroides.

Economics of ProductionIt is of little value to potential pro­

ducers to note mainland prices whenconsidering the economic feasibility forproteas in Hawaii, unless local costs ofproduction are known. Is $3 per bloomenough to pay for the cost of floweringa king protea? How many blossomscan be expected per plant per year; persquare foot of ground? The techniquesof crop production, management, andcosts are an important part of researchprojects currently underway. For ex­ample, at Kula, the average number of

Packing pincushion (Leucospermum cordi/olium) for the retail florist.

pincushions cut per plant in Decemberwas 42, in January 37 and in February45. Growers must determine their costsin order to see if commercial produc­tion is justified.

Potential OutletsThe two most widely spread proteas

in production on the Mainland todayare P. cynaroides and L. cordi/olia-m.Due to the weight, export of the kingprotea in competition with Californiais questionable. The pincuthion is an­other matter. In the spring of 1969,Southern California pincushions cameinto production from 90 to 100 daysafter the first cut in Maui. If this dif­ference persists, L. cordi/olium might

fit nicely into an early market on theMainland. It must be remembered,however, that Southern California ex­perienced unusually bad weather inJanuary and February 1969.

Certainly Hawaii must consider forits major exports other more exoticspecies and a "mixed pack" of assortedproteas that would be easier for main­land retailers to handle.

Perhaps one of the best ways to mar­ket small quantities of proteas is to mixthem in with exotic flower "packs". Ifretail outlets in Hawaii handled pro­teas, visitors would associate them withother tropical flowers that are shippedin quantity.

SOURCES OF SEEDSAND PLANTS*

G. W. ALTHOFERBox 5Dripstone, N.S.W., Australia

PETER B. DOWP. O. Box 696Gisborne, New Zealand

DUNCAN AND DAVIESBox 340New Plymouth, New Zealand

W. J. and E. R. MIDDELMANNHoningklip Nurseriesc/o Barosma, Barmbeck AvenueNewlands, Cape, South Africa

NATIONAL BOTANIC GARDENSOF SOUTH AFRICAKirstenboschNewlands, C.P., South Africa

ALBERT PRATTRaleigh StreetWaitara, New Z,ealand

GEORGE RAINEY137 Seabrook AvenueNew Lynne, Aukland 7New Zealand

MAX WILCOXP. O. Box 23Kumneu, New Zealand

*Reference to a seed or plant source does not imply approval or recommendation by theCollege of Tropical Agriculture, University of Hawaii, to the exclusion of others that maybe suitable.

22

REFERENCES

BLOMBERY, A. M. 1967. A Guide to Native Australian Plants. Angus and Robertson, 107Elizabeth Street, Melbourne, Australia.

ELIOVSON, SIMA. 1967. Proteas for Pleasure. Howard Timmins Co., Cape Town, South Africa.HARRISON, RICHMOND E. 1967. Trees and Shrubs for the Southern Hemisphere. A. H. and

A. W. Reed, 182 Wakefield Street, Wellington, New Zealand.HORN, W. 1962. Breeding Research on South African Plants: II. Fertility of Proteaceae. Jour­

nal of South African Botany 28 :259-268.LETTY, CYTHNA. 1962. Wild Flowers of the Transvaal. Hortors Limited, Johannesburg, South

Africa.MIDDELMANN, W. J. AND E. R. 1963. Growing Proteas from Seed. South African Garden and

Home. May issue.MORCOMBE, M. K. Australia's Western Wildflowers. Grandfall Press, 164 St. George's Terrace,

Perth, Western Australia.NEAL, MARIE C. 1965. In Gardens of Hawaii. Bishop Museum Press, Honolulu, Hawaii.PALMER, EVE AND NORA PITMAN, 1961. Trees of South Africa. A. A. Balkema, Cape Town,

South Africa.RADCLIFFE, WOODWARD. 1968. "The Proteas." Los Angeles Times Home Magazine, Garden Sec­

tion, July 7 :46-47.RILEY, HERBERT P. 1963. Families of Flowering Plants of Southern Africa. University of

Kentucky Press, Lexington, Kentucky.Rossouw, G. G. 1966. Proteas can be grafted. Farming in South Africa 42 (6) :53-5.ROUSSEAU, G. G. 1967. Propagation of Proteaceae from Cuttings. Fruit and Food Technology

Research Institute, Stellenbosch. Republic of South Africa, Department of AgriculturalTechnical Services. Technical Communication No. 70.

RYCROFT, H. B. 1963. Our Flower Paradise. Hortors Limited, Johannesburg, South Africa.SKYWAYS. 1968. Protea-South Africa's National Flower. South African Airways, Johannes­

burg, South Africa. November issue.STEVENS, WALLACE R. 1965. Growing S. A. Proteaceae in New Zealand. .Journal of the Bo­

tanical Society of South Africa 51:19-21.SUNSET MAGAZINE. 1969. Those Crazy Protease Menlo Park, California. 42 (4) :250-251.THORNS, F. W. 1943. South African Proteaceae in Cultivation. Journal of the Botanical Society

of South Africa 29 :9-12.VAN STADEN, J. 1966. Studies on the Germination of Seed of Proteaceae. Journal of South

African Botany 32 (3) :291-298.VOGTS, MARIE M. 1954. Growing Proteaceae in the Summer-rainfall Area. Journal of the

Botanical Society of South Africa 40: 18-21.VOGTS, MARIE. 1960. The South African Proteaceae: The Need for More Research. South

African Journal of Science 56:297-305.WERNER, H. F. 1951. South African Proteaceae and Their Cultivation. J oumal of the Botanical

Society of South Africa 37:14-17.WERNER, H. F. 1957. Propagation and Cultivation of Proteas and Heaths. Journal of the

Botanical Society of South Africa 43 :6-10.

23

PROTEAS UNDER EVALUATIONAT ~ULA, MAUl BRANCH STATION

= symbol indicates former species nalne which nlay be helpful whenworking with older plant listings. Plant names used in this publi­cation are based upon the 1969/70 Index Seminum of the NationalBotanic Gardens of South Africa.

Aulax cneorifoliaBanksia attenuata

coccineacolliniaericifoliagrandismediaoccidentalisroburspeciosaspinulosavictorial

GreviUea banksiithelemanniana

Hakea bucculentalauriana

Isopogon anemonifoliusdawsonifo~mosus

petiolarisLambertia formosaLeucadendrqn adscendens

argenteumcomosum (== aemulum)daphnoidesdiscoloreucalyptifoliumgandogeri (== guthrieae)laureolum (== decorum)salicifolium (== strictum)stokoei

tinctum (== grandiflorum)venosumxanthoconus (== salignum)

Leucospermumbolusii (== album)catherinaeconocarpodendron

(== conocarpum)cordifolium (== nutans)cuneiforme (== attenuatum)muiriireflexum

Paranomous reflexusProtea amplexicaulis

barbigeracompactacynaroideseximia (== latifolia)grandicepsharmerilacti hybridlacticolor hybridlepidocarpodendronlongifloralongifoliaobtusifoliapityphyllapulchrarepens

Serruria floridaTelopea speciosissima

UNIVERSITY OF HAWAII, COLLEGE OF TROPICAL AGRICULTUREHAWAII AGRICULTURAL EXPERIMENT STATION, HONOLULU, HAWAII

HARLAN CLEVELANDPresident of the University

C. PEAIRS WILSONDean of the College and Director of the Experiment Station

WALLACE C. MITCHELLActing Associate Director of the Experiment Station