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Christmas Bells : Cutflower Cultivation containers fertilising habitat harvest & packaging maintenance potting mix seedlings
Plants can be grown from seed and usually take three years to flower. Older plants can be divided to obtain new plants. Plants have also been tissue cultured, but so far this approach has not produced the advantages sought of vigour nor evenness of growth. Blandfordia is a protected species, and a license (from NPWS) is required to pick either flowers or seeds. The permission of the land-owner is also required. Picking from National Parks is prohibited, and heavy fines apply. A license is also required to sell Blandfordia, or any other protected species, in NSW. Growth in the seedling stage is slow, and 4-5 months will pass while the seedlings reach 5-6 cms. tall. Perhaps the reason why nature provides such prolific seeding of Blandfordia is the slow and hazardous establishment process which the plant must confront in nature. Blandfordia seedlings are slow growing with little ability to adjust or to correct their posture. But they are extremely tenacious. So a plant, poorly established with bent roots and one or more leaves buried, may not prosper, but will not die. It could still be there, 6 cms. high, after several years when its siblings are flowering. Added to this is the enormous variability of seed-grown plants. Even after good, equal care some plants will remain small while others will leap forward. With most plant species, selection of the best specimens at transplanting is
recommended. This is a reasonable rule with Blandfordia also. But with Blandfordia, thin
seedlings ( from overcrowding) or young plants which have stopped (from hard conditions)
can still recover and make excellent growth. Seedlings can be picked out from the germination trays once they have reached 6-7 cms.
height. Or, if necessary, they can remain for as long as a year and still become good
plants. As with some other species, transplanting invigorates Blandfordia plants in a way
which is not understood. But taking them out and clean-rooting them and replanting can
stimulate them. The preferred growing medium for Blandfordia is again a mixture of almost entirely
equal (by volume) quantities of peat and coarse clean sand. The pH should be in the range
of 5.0 -5.5, and lime and dolomite are used to achieve this. A range of fertilisers can
also be incorporated into the mixture. Of course, even though some of these are slow
release types, they will be of temporary value and a sound fertiliser regime should be
followed (see Fertilising below). CONTAINERSA range of pots and other containers (e.g. polystyrene boxes) have been used to
transplant into from the seed trays. Our best results have come from using the 50 x 50 mm
square forestry tubes, which are 120 mm deep. A single plant is placed in each tube.
Results with direct transplant to containers larger than this have been poor; the
relatively slow growth rate would also result in poor utilisation of media and fertiliser.
Results using 75 mm round tubes (110 mm deep) improved when two, not one, plants were
placed in each tube (conjecture is that the off-centre plants are nearer the edge of the
container and profit from greater oxygen levels or perhaps warmth). Results with
polystyrene boxes were fairly satisfactory when slightly older seedlings were planted at
40-50 mm spaces in regular rows in them. After 12-15 months in these nurturing containers we have planted the well-grown plants
into 5-7 litre plastic planter bags, with 3 plants per bag. We now have plants which have
been four years in such bags and their crowding and root-bound condition is apparent.
However so far we have not noted any decrease in flowering. Recently we began planting
well grown seedlings (2 years old) into beds of mix 200 mm deep at densities of around 65
/m2. MAINTENANCEWatering and weed control require attention. Older plants need less frequent watering,
but the species has a considerable need for water, especially during budding and
flowering. Through the summer daily watering is required, but in the winter the need is
less. Weeds can become a problem. Blandfordia does not compete well and can be choked out
especially by stoloniferous invaders. Hand-weeding before a problem develops is ideal.
Some work has been done by us with pre-emergent herbicides and one - Rout - has proven
valuable but tricky to use Liverworts and moss growth can also be harmful, especially for young plants. Control of
watering with as long as possible intervals between applications (e.g. watering large pots
only once every three days in winter) can prevent moss development. There is a very
effective moss and liverwort killing chemical on the market, its only drawback being its
cost (about $40 per litre, which cannot be diluted very far). Occasionally damage from fungi occurs. Again over-wet conditions favour such
occurrences. The worst hazard encountered has been Botrytis attacks of blooms in the field
or during shipment in hot humid periods. Current approaches to pre-package storage involve
higher cool-room temperatures to avoid later tissue damage in transit which may
pre-dispose the fungal onset. FERTILISINGAlthough Blandfordia in the wild grows healthily in poor soils, it can do much better
in cultivation with a suitable fertiliser regime. The plants' requirements and appropriate
compounds for supplying them were described by Lamont, Cresswell and Griffith in
Horticultural Science Vol. 25 (11) pages 1401-1402, 1990. If plants do not receive enough fertiliser not only is their growth retarded but their
roots will have a mass of fine fibrous "seeking" rootlets. On the other hand
over-fertilised plants can become distorted, with unnaturally large leaf bases and flower
stems up to 2.5 cms. thick. Such plants will also have short fat storage roots and little
other underground development. A two-part soluble fertiliser is used, avoiding the
precipitation of other salts with calcium nitrate. Regular application at fairly low
concentrations is giving excellent results. HABITATSome shade has been recognised as necessary for Blandfordia to do well in a
mono-culture state. How much shade will provide adequate conditions for the plants and
optimum conditions for the flowers has not been accurately determined, and, indeed, will
probably vary with locality. Too much shade definitely gives paler flowers, as well as
providing for excessively moist conditions with the disadvantages already discussed.
Flowers are also protected against birds and strong winds. HARVESTING AND PACKAGINGThese have received a lot of attention, much of it already in the public domain (e.g. in Australian Horticulture May-June 1993). More development work is proposed for this year. However, the current practices do meet the needs of the flowers, and the report from Aalsmeer, Holland, was that the condition of the flowers received there was excellent. The need is for simpler, quicker, cheaper approaches which achieve the same level of protection. Blandfordia Potting Mix : 25% composted pinebark fines 25% peatmoss or 25% composted hardwood sawdust 50% washed river sand plus fertilisers per m3 : 1.50 kg Osmocote 18 : 2.6 : 10, 8 mth. 0.70 kg coated iron 0.15 kg dolomite 0.30 kg lime 0.50 kg. Osmocote 0 : 0 : 37, 6 mth. controlled release potassium sulphate (omit if unavailable and increase Osmocote from 1.5 to 2.0 kg./m3) Liquid fertiliser : per 100 litres calcium nitrate 87g CaNO3 iron chelate 1.3g FeEDTA mono potassium dihydrogen phosphate 6.8g KH2PO4 ammonium nitrate 2g NH4NO3 potassium sulphate 32.3g K2SO4 magnesium sulphate 25g MgSO4 This liquid fertiliser mix is from NSW Agriculture research, in Nutritional studies of Christmas Bell by G.P. Lamont, G.C. Creswell, G.J. Griffith; Hort.Science 25(11)1401-1402, 1990. Check EC (conductivity) of mix leachate and keep below 0.75 dS/m; we had root disease problems in the past which appeared to be associated with mix salinity levels that were normal for other crops but seemed to be too high for Blandfordia, which is a slow-growing, low mass plant. These notes are intended as a guide only. Crops will have different reactions to different climatic & site conditions. Intending growers are urged to plant a small crop initially to check its viability in their particular area. These crops are mostly relatively new to cultivation, and aspects of their successful cultivation remain speculative. We can take no responsibility for differences in plant characteristics or management needs that growers may find. © Gordon Dick And Paul Dalley 1994 |
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Blandfordia grandiflora occurs in Eastern Australia from Hervey Bay to
the Hawkesbury River, mostly on coastal sandy plains, but with colonies in unexpected
places such as on Gibraltar Range, or into the mountains near Bilpin, or occasionally in
coastal forests on heavier soils. Soils are usually high in organic matter. The flowers,
which vary from dark red with yellow edging to all yellow, are produced mostly between
November and February, but some may be found throughout the year. The longevity of plants
has not been determined, nor has the potential for producing flowers.