[Front Page] [Features] [Departments] [SGAP Home Page] [Subscribe]

Australian Plants online


Propagation and Cultivation of Flannel Flower

Cathy Offord and Joanne Tyler

Of the fifteen species of the genus Actinotus, fourteen are Australian endemics and one occurs in New Zealand (Powell and Wiecek, 1992). They are all called Flannel Flower but the best known, and arguably the most horticulturally attractive species, is the Sydney Flannel Flower (A. helianthi). This species occurs from central and south eastern Queensland (Carnarvon and Isla Gorges) down to the south coast and western slopes of New South Wales (out to the Pilliga Scrub). A very similar rare species (A. schwarzii) occurs in a few sheltered areas in the MacDonnell Ranges of the Northern Territory, growing mainly on precipitous cliff faces. Other Flannel Flowers of horticultural interest include the Pink Flannel Flower (A. forsythii) and the Western Australian White Headed Flannel Flower (A. leucocephalus).





The small individual flowers in the inflorencence of Actinotus helianthi are surrounded by petal-like bracts. Select the thumbnail image or plant name for a higher resolution image (24k).



Flannel Flowers are predominantly white, cream or greenish in colour, although Actinotus forsythii has pinkish-purple flowers. The inflorescence is a daisy-like structure that consists of a simple umbel surrounded by radiating woolly bracts. It is the arrangement of the bracts that leads to the generic name from the Greek Actinotos, meaning 'furnished with rays'.

In this paper we will refer to Actinotus helianthi (the Sydney Flannel Flower), as Flannel Flower unless otherwise stated.


Flannel Flowers as Cut Flowers

Flannel flowers are eminently suited for the cut-flower market because of their long stems (up to 60 cm), colour, texture, and regular appearance. The foliage is a soft silvery grey-blue and attractively complements the inflorescence. Flannel Flowers have a long vase life which is important in the cut-flower trade. The vase life of one selection we picked was nearly two weeks.

Flannel Flowers are prone to stem air embolisms when cut. Embolisms may significantly reduce vase life and thus the stems must be placed directly into water after cutting. Blooms should be harvested when the lower flowers on the umbel are just beginning to open and the vase life may be extended by overnight treatment in 1% sucrose and 0.5% citric acid (Watt, quoted from Maddock,1990).

The Flannel Flower is very attractive in many sorts of floral arrangement and in particular makes a very useful wedding bouquet flower. It dries well if picked before the florets form seed and is very attractive as a pressed flower.

The flowering period is from August through to March with peak numbers occurring in September in some areas. We have observed that flowers produced earlier in the season are larger and more numerous. Over 200 inflorescences have been observed on one plant during the early part of the season. Harvesting these may bring on a second flush of flowers.

If the first inflorescence is pinched out early, a spray of blooms is produced on the main peduncle, similar to spray carnations. The result is very attractive and has great potential for the cut-flower market. It would also be a good way of presenting plants for the potted market.


Flannels as Pot Plants

Flannel flowers make excellent pot plants and they are well suited to grow on a sunny terrace or as a temporary house plant display. They can look a bit bedraggled around the base after the end of each growing season, but stripping the bottom leaves will rectify this.

We use a mixture of sand, perlite and peat (10:4:3), and we are starting to used coir fibre as an alternative to peat. The proportion of coir used is less than peat because of the higher water holding capacity of coir. Other freely draining potting mixes could be used but care might be needed to avoid high levels or imbalances of nutrients. Pot plant nutrition is an area for further research. We fertilise the plants with slow release low phosphorus fertiliser (a 1:1 mixture of Nutricote Purple and Blue) and the occasional iron supplement at the recommended rate will avoid yellowing. If yellowing does not disappear then drainage is likely to be the problem. Flannel flowers may last up to three years in a pot if properly cared for.






A massed display of Actinotus helianthi on coastal dunes on the central coast of New South Wales. Select the thumbnail image or plant name for a higher resolution image (34k).


As a Garden Plant

There are some indications that Flannel Flowers can grow in a variety of garden situations, provided the soil is freely draining, not too rich and there is some sun. For example, one of us has had success growing a couple of plants in a herb garden, where they seem to appreciate the dry conditions and the protection afforded by other plants. They can be a little temperamental and it is worth trying a number of different positions and watering regimes.

According to Wrigley and Fagg (1986) coastal type Flannel Flowers can succumb to frosty weather in Canberra. They suggest trying Blue Mountains types in colder areas.


Cultivation Characteristics

Actinotus species occur in a wide range of soil and climatic types. The Sydney Flannel Flower grows naturally in full sun or semi-shade on shallow sandy soils in dry sclerophyll forest, coastal heath or scrub. They will grow a wider range of soils provided that there is excellent drainage. Pruning will improve flowering and prevent the plants from becoming too leggy.

The most commonly seen type is rather straggly and can reach a height of more than one and a half metres. A distinctly different type is found on exposed coastal headlands and dunes, being shorter (up to one metre), and bushier with fleshier leaves. The size of the flower varies greatly from 2 cm to 10 cm. Many of these differences persist in cultivation. We are assessing and collecting living representatives of this type of natural variation. This germplasm will be used in our future studies of Flannel Flowers, which will include selection and breeding, as well as research into cultural aspects.

Flannel Flowers grow well for up to four years in cultivation. Research is required to determine if there are any factors which may extend the life of plants beyond this. In our work so far we have observed that in terms of the number of flowers produced, the second and third years after propagation are superior.

Some Flannel Flowers species, such as Actinotus forsythii, are annual or biennial and currently not suitable for cut flower production. This species has some potential as a bedding plant, but propagation is a problem. Seed germination is difficult (Table 1) and vegetative propagation is also difficult due to the rosette shape. We have had limited success with tissue culture of this species but much more work is required.


Bush Picking

As Flannel Flowers are protected by National Parks and Wildlife legislation, the amount of cut-flowers that can be harvested from the bush is limited. Bush picking is not a desirable practice anyway because it depletes seed reserves and the quality of the flower is very poor. A problem with bush-picked Flannel Flowers is that the stems are often spindly and weak. Another problem is that they must immediately go into water to stop the formation of embolisms. An alternative to bush harvesting is to cultivate plants in plantations and this requires further research.


Seed Germination

Seed germination of Flannel Flowers is unreliable. Sometimes they will germinate very easily and other times not at all. Lighting a small fire over the seeds in a punnet or lightly burning the seeds over a naked flame is said to improve germination, possibly by breaking down the impervious seed coat (Blombery, 1965; Elliot and Jones, 1982). We have had limited success with such methods. Sometimes the seeds will germinate after being left for a long period of time in a punnet (up to one year in some cases). The role of the seed coat in germination needs to be investigated further.

Table 1 shows the results of an experiment conducted on germination of various Flannel Flower seed collections.


Table 1 - Seed germination (%) of Actinotus spp. in different temperature (degrees C) and light regimes (experiment completed March 1993)
SpeciesSource12C
Light
12C
Dark
20C
Light
20C
Dark
28C
Light
28C
Dark
A.helianthiCultivated - Late 19926468646008
A.helianthiWild - Late 199188886056428
A.leucocephalusWild - 19901600121212
A.forsythiiWild - Early 1992000000


It is apparent from these results that for Actinotus helianthi at least, temperature may play a role in seed germination. Flannel Flowers do not seem to be light sensitive but this requires further investigation.

The University of Sydney is doing an extensive study of seed germination of Flannel Flowers. They have found that like many other members of the family Apiaceae, there is a high proportion of embryo-less seeds in Actinotus helianthi (possibly up to 10%). The rest are in a state of dormancy and the study is looking at factors affecting this.

One factor appears to be time. Seeds sown directly after collecting are purported to be very regenerative (Elliot and Jones, 1982). It is not always possible to sow seeds immediately and after this initial phase they appear to require an after-ripening period which may be months to years. Massive numbers of Flannel Flowers germinate following bush fires in some areas, indicating that the seed has good longevity. Environmental conditions are obviously important for germination, but the specifics are difficult to determine. Storage conditions may also have an important role. In years to come it may be possible to breed dormancy out of Flannel Flowers but presently, dormancy is the single most important problem affecting seed propagation.


Vegetative Propagation

Flannel flowers are easily propagated from cuttings taken from cultivated plants. The main advantage of cuttings is that good selections can be propagated, a factor which will be important in the development of Flannel Flowers as a commercial crop.

We have been able to propagate up to 150 large cuttings from one well grown stock plant. The number may be increased if the plant was to be sacrificed or, possibly, by manipulating nutrition (this needs investigation).

From the Royal Botanic Gardens database we determined that the optimum rooting treatment for A. helianthi is IBA in the concentration range IBA 2000 - 3000 ppm. The strike rate using this treatment, depending on time of year, usually exceeds 90%. Actinotus helianthi will also strike when no auxin is used, albeit more slowly. For our propagation experiments we have used Clonex Purple formulation (IBA 3000 ppm) and steam sterilised propagation mix containing perlite, sand and coir (4:1:1).

The following tables (2 and 3) summarise the results of a propagation experiment that we conducted in Autumn 1993.


Table 2 - Effect of humidity and cutting type on rooting and survival of cuttings of Actinotus helianthi (clonal accession 900461). Measurements were taken eight weeks after propagation.
Humidity
Regime
Cutting TypeNumber
Rooted
Number Cuttings
Survived (rooted
and not rooted)
Replicates (number
of punnets containing
nine cuttings)
FogStem48a49a12
Tip (apex cut out)74b81bc12
MistStem66ab66ab12
Tip (apex cut out)88b100c13

Numbers with the same letters are not significantly different according to Fishers LSD test (P>0.05).



Table 3 - Effect of humidity regime and cutting types on root quality and shoot number of Actinotus helianthi (clonal accession 900461). Measurements were taken eight weeks after propagation.
Humidity
Regime
Cutting TypeAverage Root
Quality (scale
of 0 to 5)
Average New
Shoot Number
Replicates (number
of punnets containing
nine cuttings)
FogStem3.25a1.73a5
Tip (apex cut out)3.93a2.15a5
Tip (apex left intact)2.82b0.2b5
MistStem3.81a1.51a5
Tip (apex cut out)3.02ab0.735
Tip (apex left intact)1.560b5

Numbers with the same letters are not significantly different according to Fishers LSD test (P>0.05).


These results show that mist is superior to fog propagation, and that tip cuttings (with the very soft apical section excised) are the best type of cutting in terms of rooting and survival. The number of new shoots is probably not important at this stage but may be later in the hardening and growth phase (we are monitoring this).

The root systems of vegetatively propagated Flannel Flowers are very delicate and roots may be easily damaged during potting up. We are observing the growth of cuttings from this experiment to determine whether this type of damage is deleterious to the survival and growth of plants. If this turns out to be the case, it might be worth treating the cuttings as plugs, and to pot them up without disturbing the roots.


Tissue Culture

Tissue culture propagation (micropropagation) of Flannel Flower selections is an alternative to vegetative propagation if very large numbers of plants from superior selections are required. Tissue cultured plants may also be more vigorous than cutting propagated plants. We have not tested this yet for Flannel Flower, however, it is often the case in other species. In preliminary studies we have found that Flannel Flowers grow quite well on full Murashige and Skoog medium with 5 uM BA (benzyl adenine) and 0.2 - 1 uM IBA, incubated at 25 degrees C and 60 umol/sqm/s illumination. A multiplication rate of three to six times can be expected after incubation of the cultures for six weeks. We are presently conducting a large experiment investigating the effect of a range of growth regulators.

Flannel flowers are strongly apically dominant in tissue culture and the apical bud must be excised for multiplication to occur. We have found this to be the case at concentrations of cytokinins high enough to elicit gross multiplication in many other plants. Vitrification (glassiness) can be a problem, however this can be overcome by not overcrowding the vessel with explants, and we therefore use large glass jars (375 ml).

We usually 'direct root' microcuttings from tissue culture. The cuttings are dipped in softwood IBA powder (liquid dips are too harsh on tissue culture material), then placed into cutting mix in small individual punnets to avoid the risk of fungal contamination and minimise root disturbance on potting up. The cuttings are left under high humidity (either mist or fog) for several weeks. Care should be taken to remove any necrotic material from around the plants and the area should generally be kept clean. Good rates of establishment (>80%) are obtained by these methods and we are investigating techniques for increasing rooting and survival.


The Future

A great deal of work still needs to be done in understanding the propagation and culture of Flannel Flowers. We know quite a bit already, but if the plant is to be developed to its full potential, then we need to know more about its likes and dislikes. Breeding will play a very important role in the future. It could take many years, but it should be possible to breed bigger and better flowers, perhaps with colour variations. For the meantime, it would be worth considering the Flannel Flower as an unimproved plant, with known limitations, that can be managed and manipulated to give a very worthwhile product.



Acknowledgements

We are indebted to Faye Cairncross for technical assistance, Paul Dally for information on field cultivation and markets, Lyn Lee (University of Sydney) for information on seed germination and Tracey Armstrong for proof reading.

References

Blombery, A. (1965). The genus Actinotus. Australian Plants, 3: 63-65.
Elliot, W.R., Jones, D.L. (1982). Encyclopaedia of Australian Plants, Vol 2, Lothian Pty Ltd, Sydney.
Powell, J.M., Wiecek, B.M. (1992). Actinotus. In: Flora of New South Wales, pp.93-94, Harden, G.J. ed., New South Wales University Press, Sydney.
Maddock, E.. (1990). Origins: Flannel Flowers, The Flower Link, 8 (90):39-41.
Wrigley, J. W., Fagg, M. (1988). Australian Native Plants. Third Edition, Collins, Sydney.



This article is a reproduction of a paper presented by Cathy and Joanne at the SGAP 17th Biennial Seminar, Robert Menzies College, Sydney, 27 September to 1 October 1993. Cathy is the Horticultural Research Officer at the Mt Annan Botanic Garden, Campbelltown where she is responsible for the implementation of research programmes. Joanne is a Technical Officer in horticultural research, also at the Mt Annan Garden.

Since this article was written, the Botanic Garden has received a grant from the Rural Industries Research and Development Corporation to work specifically on the development of Flannel Flowers as a cut flower crop for export. The grant covers three years of research. Trials with selected growers around New South Wales have commenced.

Ruler
[Front Page] [Features] [Departments] [SGAP Home Page] [Subscribe]

The Society for Growing Australian Plants