The
              Report

No. 45: Acacia has promising potential as export cut flower crop


The full report
This is a summary of two RIRDC full reports (DAV-91). The first "Developing native Acacia species as an export cut flower crop" is by Francha Horlock, John Faragher (ph 03 9210 9222, Fax 03 9800 3521) and Peter Franz of Agriculture Victoria’s Institute of Horticultural Development and Rod Jones of the National Flower Centre, Melbourne Markets. The second "Acacia cut flower and foliage production" is by Francha Horlock, John Faragher and Rod Jones. Copies of these full reports ($10) are available from RIRDC on 02 6272 4819, fax 02 6272 5877.

Market research, optimal plant propagation, and development of special post harvest handling techniques to increase vase life, have resulted in successful test marketing in Japan of Acacias as an export cut flower crop.

A project partly funded by the Rural Industries Research and Development Corporation (RIRDC) set out to select the Acacia species most likely to be commercially successful on export markets.

Although there are approximately 700 species of Acacia endemic to Australia, very little is grown here as cut flowers or foliage. Ironically, Acacia has proved successful in Europe, grown in southern France and Italy, and sold as a cut flower under the name of Mimosa.

Its success as a cut flower in Europe indicates the huge potential of this genus as a commercial crop in Australia, particularly when it is considered that the European industry is based on only two or three species, grown under adverse conditions on grafted rootstock.

The research was undertaken by Francha Horlock, John Faragher and Peter Franz of Agriculture Victoria’s Institute for Horticultural Development, Knoxfield; and Rod Jones of the National Flower Centre at Melbourne Markets. Their report to RIRDC: Developing native Acacia species as an export cut flower crop, was one of two papers on Acacias.

Horlock, Faragher and Jones also published Acacia cut flower and foliage production, which looked at the potential of Acacias as cut flowers, and best methods of propagating, germinating and cultivating the species.

This second report also discusses pests and diseases, postharvest care, export requirements and the economics of growing Acacias as a cut flower crop.

The Study

Market research was undertaken in Japan to determine the Acacia species most likely to be successful there. Japanese flower importers and consumers were shown a series of high quality colour photographs and asked to select the colours and morphologies of flowers and leaves they most preferred.

The Japanese preference proved to be for "ball-shape" flowers. While no preference was given on leaf shape, spiky, triangular leaves were popular.

Heavy scent common in many Acacia species was not wanted and importers expressed a clear preference for pale, lemon-coloured flowers delivered from July until early November. Europe’s darker yellow-orange Acacia flowers are sold as Mimosa in Japan from mid-December until May.

Mimosa also is currently grown locally in the Chiba area between Narita Airport and Tokyo. The Japanese growers supply the market from January until April.

This shows there is considerable opportunity for the Australian product in the Japanese Autumn period from September until mid-December.

After preferred forms of Acacia were identified in the market survey, propagation and cultivation techniques were determined. Stem cuttings from 19 species were chosen for propagation.

The stem cuttings were propagated using softwood tip cuttings approximately 12cm in length.

Two-thirds of the leaf area was removed from the lower part of the cutting. Each of the remaining leaves were cut in half and the cuttings were dipped sequentially in 1.5% sodium hypochlorite, 1.5ml/L PrevicureÒ and 10,000 ppm indole-3-butyric acid for five seconds.

They were then allowed to air dry for 30 seconds before being placed in a propagating mix of one part coarse river sand, and one part each of peat and perlite.

The cuttings were then placed into a mist bed propagator which produced five seconds of mist every 60 minutes, with bottom heat set at 250C.

Strike rates were 1% to 91% in 16 to 48 days.

Species of Acacia propagated successfully from stem cutting
 
Species Number of clones collected Source of material
A. acinacea
2
  
A. boormanii
4
 Domestic garden, Melbourne
A. buxifolia
1
 Prof. M. Sedgley, Darebin Creek Park, Melbourne 
A. caesiella
1
 Royal Botanic Gardens, Canberra
A. myrtifolia
2
 Natural population, Kalorama, Melbourne
A. pravissima
2
 Arboretum, LaTrobe Un.v.
A. stricta
1
 Arboretum, LaTrobe Un.v.

Sixteen Acacia species were selected for seed germination. The seeds (see table below) were scarified by placing them for one-minute into water which had just been boiled. They were then taken out and surface sown over a commercial seed raising mix.

Extra seed raising mix was sieved in a fine layer over the treated seed and the seed was watered in. Seeds were placed in a glasshouse maintained at a minimum temperature of 50C. Micro spray watering was set to come on twice a day for 20 minutes to encourage germination.

Seed germination details for Acacia species
 
Species
Seed merchant
Seed batch number or provenance
Seed pre-treatment method
Germination rate (%)
Number propagated
A. acinacea
Goldfields Revegetation
Maryborough
Boiled water, one minute
0
0
A. baileyana purpurea
Nindethana Seed
NS-11335
Boiled water, one minute
7
25
A. boormanii
Nindethana Seed
NS-9876
Boiled water, one minute
0
0
A. brachybotrya
Gold Fields Revegation
Whipstick
Boiled water, one minute
30
12
A. buxifolia
Nindethana Seed
NS-6896
Boiled water, one minute
50
168
A. elongata
Nindethana Seed
N/A
Boiled water, one minute
62
30
A. gladiiformis
Nindethana Seed
N/C-00701
Nicked
30
15
A. iteaphylla
Nindethana Seed
NS-8390
Boiled water, one minute
26
77
A. meisneri
Nindethana Seed
N/A
Boiled water, one minute
42
21
A. merinthophora
Nindethana Seed
NS-6340
Boiled water, one minute
92
48
A. pravissima
Nindethana Seed
NS-11751
Boiled water, one minute
55
84
A. rubida
Nindethana Seed
NS-6898
Boiled water, one minute
90
35
A. salkiciformis
Nindethana Seed
NS-7507
Nicked
42
20
A. silvestris
Nindethana Seed
NS-230
Boiled water, one minute
32
15
A. stricta
Nindethana Seed
NS-10626
Boiled water, one minute
17
58
A. uncinata
Nindethana Seed
N/CI
Nicked
28
15

Following the propagation and germination trials, plants were grown in a potting medium of pine bark, coarse sand and brown coal. Once the cuttings had struck and seeds had germinated, the plants were placed into 75mm tubes containing the above potting media and maintained in a glasshouse with minimal heating for three months.

The glasshouse was maintained above a minimum temperature of 50C and near ambient humidity with ample air movement. After being placed outside for two weeks under 70 per cent shade, the Acacias were planted into trial plots at the Institute of Horticultural Development, Knoxfield, near Melbourne and at five commercial flower farms.

The trial plantings were conducted under regular management practices on each farm. They were assessed for a range of growth and flowering characteristics at six and 12 months from planting, with measurements covering plant height, number of stems above 60cm, the flowering time and the plant health.

Postharvest treatments to trial bud opening solutions and increase vase life were assessed. These included a range of wetting agent solutions and pulses, germicide solutions, glycerol solutions, glycerol pulses, gibberellic acid pulses, cobalt chloride pulses, silver nitrate dips and stem cutting techniques.

Figure 1. Effect of bud opening treatments on flower opening (% open inflorescence) in Acacia retinodes. Branches were pulsed for 16h at 10, 20 or 30oC with the following solutions: deionised water; 1% sucrose + 50 mg/L chlorine; 0.01% Agral + 200 mg/L aluminium sulphate; or 0.01% Agral + 200 mg/L aluminium sulphate + 1% sucrose. After pulsing, branches were placed in deionised water.

B. Vase life of Acacia branches after treatment with bud opening solutions. 
Bar represents lsd at P = 0.05.

The next stage was to develop methods of packaging and transport for the Acacias.

This included various solutions and mediums for both wet through to dry transport. Various plastic wrappings and liners for flower bunches inside fibreboard boxes also were compared.

Insect disinfectation trials were conducted on Acacia flowering stems at the yellow bud stage. Three fumigants were trialled to see the impact they had on the flower life and their effectiveness in killing insects.

Figure 7. Effect of fumigation on the total life (days) of Acacia iteaphylla. Branches were pulsed in 0.01% Agral + 200 mg/L aluminium sulphate + 1% sucrose and stored at 18oC for 16h during fumigation. Branches received: no fumigation, 16h fumigation with Pestigasâ + Phosfumeâ , 2h fumigation with methyl bromide and 2h treatment with Pestigasâ + Insectigasâ . After fumigation all branches were subjected to a simulated transport period of 2 days at 15oC and then placed in a 1% sucrose + 50 mg/L chlorine solution at 20oC for vase life assessment. Bar represents lsd at P = 0.05

When the fumigation tests were completed, two trial shipments of two varieties of Acacia – A. cultriformis and A. retinodes – were sent to Japan for assessment by Japanese importers and florists.

The results

The most promising Acacia species tested included A. buxifolia, A. pravissima, A. retinodes, A. baileyana, A. cultriformis. It was established that flowers were best picked in bud, with five per cent and 20 per cent of inflorescences/buds open. The research also found that a pre-transport preservative pulse of 0.01 per cent Agral, 200 mg/L aluminium sulphate and one per cent sugar in water over 16 h, opens flower buds and extends export flower life from three to 10 days.

For best results during transport, the flowers were wrapped in perforated sleeves or polyethylene box liners, with the stem ends placed in moistened floral foam. Then the flowers were packed in fibreboard boxes.

After transport, to optimise flower life, stems should be recut and placed in a standard commercial preservative solution.

Stems of A. retinodes were well received by Japanese florists in the trial marketing exercise in February 1997 and successful disinfestation was achieved using InsectigasÒ and PestigasÒ .

The report says that in the immediate future, market research, trial plantings, export trials and promotions are needed. At the same time, long-life species and clones need to be selected and planted.

The project cost a total of $377,000 (RIRDC provided $157,322 plus 10 per cent overheads, the industry gave $45,000 cash and in-kind, and Institute for Horticultural Development $159,000).

The report says that if Australia can sell at least 500,000 stems a year at a profit of $0.25 per stem, from 1999-2000 to 20009-2010, the accumulated profit will be at least $1.25 million.

While the researchers identified intellectual property issues – knowledge of markets, plant production, post-harvest handling and marketing developed during the project – they believe the information should be in the public domain for Australian industry to exploit.

The trial plots at the Institute for Horticultural Development and elsewhere are open for inspection, and Francha Horlock and John Faragher are available to discuss Acacia with anyone interested.

At least three exporters are interested in the crop – Bruce Cameron (Austwinds International), Shaun Keenan (Floratrade International) and Brian Harris and Peter Brooks (Collina Exports).

Summary

The Japanese market appears eager and ready to buy good quality, Australian-grown Acacia flowers which have a total life span of more than seven days in Japan.

For Australian-grown Acacia to be successful on the international market, the flower industry must adopt the recommended postharvest treatments and select clones with long flower life.

The researchers plan to assist exporters with further trial shipments and believe also that good quality Acacia should be promoted on local flower markets in Australia. Another outcome of the research has been the publication of an Acacia production manual.

Contact RIRDC for more copies of this Short report

PO Box 4776, Kingston ACT 2604
Tel: (02) 6272 4539
Email: rirdc@rirdc.com.au
Internet: http://www.rirdc.gov.au

Other RIRDC Wildflowers and Native Plants  reports: