Hortfact gypsophila For Cut Flowers Propagation, Production and Harvesting John Elgar




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HortFACT - Gypsophila For Cut Flowers - Propagation, Production and Harvesting



John Elgar - HortResearch, Mt Albert



  1. General Requirements

  2. Propagation

  3. Planting Programmes

  4. Plant Management

  5. Postharvest Care

  6. References

  7. Acknowledgements

Two forms of gypsophila are cultivated: the annual Gypsophila elegans, and the perennial Gypsophila paniculata. The perennial form, G. paniculata 'Bristol Fairy' is most in demand on international and local markets, though several new cultivars are now available (e.g. 'Bridal Veil', and the Danniger cultivars).

Gypsophila is used traditionally as a filler for formal floral arrangements and bouquets, especially with roses. With the increase in availability of alternative products (e.g. various forms of limonium, foliage, ferns, grasses), demand for gypsophila has dropped. Most NZ-grown product is sold on the local market, with export demand having fallen from $0.5M to $0.1M over the last decade.

Some export crop is still sold to niche markets in Japan, Singapore, New Caledonia, and the Pacific Islands, but it is now considered to be an "old-fashioned" flower. New cultivars, such as those supplied by Danniger (Israel) may lift the image of the crop, but many of these are considered to be too sparse and large for floral bouquets.


General Requirements


By choosing the correct growing district, or by manipulating the environment, G. paniculata can be flowered throughout the year.

Gypsophila paniculata demands a free-draining, preferably calcareous soil. Gypsophila, especially when left in the ground over winter, does not tolerate "wet feet" as it is susceptible to Phytophthora root rots.

If the crop is to be grown outdoors, good shelter is necessary. Hot dry winds or untimely rainfall will cause browning of flowers. Protection will benefit the crop. During summer, a simple roof of either plastic or acrylic material will protect flowers from rain and weather. Shade may also be desirable.

For out-of-season production, greenhouses will be required so that supplementary light and heat can be supplied (see below). Because the crop can become dense, hot air systems are suitable to disperse heat throughout the crop. Provision must be made for packing facilities and a coolstore.

Propagation


Gypsophila can be propagated by tissue culture, or alternatively, growers may propagate gypsophila vegetatively from tip cuttings.

Growers are advised to maintain a stock house purely for the purpose of obtaining-healthy cutting material. The stock house should contain plants that have been selected as being the most productive and true to type. For cuttings to be available throughout the year the stock house must be provided with both heat and light.

As temperature and day length decrease, gypsophila tends to rosette. This can be considered as a stage of dormancy (or non-growth), and cuttings taken from 'rosetted' plants will form roots only with difficulty.

Cuttings should be snapped from the stock plant in a similar way to carnations. Cuttings should be taken at the 6 - 8 leaf stage, before flower initiation has occurred. They should be treated with a rooting hormone powder and inserted in the propagating mix under mist with base heat. The rooting medium must be well drained and well aerated. Pulverised bark is satisfactory. Propagation takes 3 - 4 weeks.

The cultivar G. paniculata 'Flamingo' will not grow readily on its own roots. Grafting on to G. paniculata 'Bristol Fairy' can overcome this problem.

Planting Programmes


Gypsophila flowers naturally outdoors in New Zealand, with heavy flushes during December-January.

Gypsophila paniculata 'Bristol Fairy' takes approximately 120 days from a spring planting to flowering, and 90 days from pinching. Stocks tend to be used for 2 - 3 years.

With the use of protected structures and supplementary heat and light, all-year-round continuity of supply can be achieved by the methods listed below. Note that flowering given for outdoor crops may vary between districts.



Natural flowering January-April from cuttings:
Cuttings are taken and placed on the bench during July. Once rooted, they may be held in the greenhouse in containers for successive planting outdoors at 3-weekly intervals from September through to late November.

Natural flowering November-February from crowns:
One year old or older crowns, if left in the field, may begin flowering as early as late November, extending through to February-March.

Second flowering from crowns, May-June:
Crowns which have flowered in the field during their natural season, from November-February, can be cut down in early February and forced, under a cloche or other protective structure, to flower during May-June.

Flowering June-October from crowns lifted late summer and coolstored then forced:
Corms can be lifted January-February, the stems and leaves removed, and the crowns placed in polythene bags, which should not be sealed. The crowns are then held in the coolstore at 2.5°C for 60 days. Dipping the crowns in benomyl (e.g. Benlate) prior to storage is suggested to reduce the likelihood of rot pathogens. Crowns are planted under cover from March. Heat and supplementary light are required.

Flowering April-November from cuttings planted in the greenhouse in autumn:


Cuttings are taken and rooted from vegetative stock plants during late summer to early autumn. A succession of plantings in separate greenhouses could give continuity of supply throughout the winter months, but once again heat and supplementary light are required.

Plant Management


Density:
The best plant density is approximately 3 - 4 plants per sq. m. Plants are spaced in double rows, with 90 cm between rows and 35 - 40 cm within the row.

Support:
A single net is placed over the crop immediately after planting to encourage tall straight stems. The net should be held at a height of about 20 cm. Wires on both sides of the bed provide additional side support at heights of 60 cm, and if necessary, 100 cm. Shoots that grow out into the aisles should be regularly trained back inside the side wires.

Pinching:


First year stocks of gypsophila require pinching, with the removal of the main central lateral. This results in a more uniform development of the remaining shoots. The shoot is pinched at the fifth to seventh node.

Postharvest Care


Gypsophila should be harvested when 50% of the flowers on the stem are open. They are generally bunched and sleeved with 5 stems per bunch. Growers will need to check on bunching and packaging requirements with the auction house or exporter they supply.

Gypsophila has a relatively short vase life if improperly handled. It is sensitive to exposure to both ethylene in the environment and ethylene produced by the flowers themselves. The symptoms are early senescence of the flowers (drying) and flower drop. However, longevity of over 2 weeks can be achieved when flowers are pretreated with silver thiosulphate (STS) at 4 mmoles per litre for 30 minutes, and then held in a solution containing 200 ppm Physan (a proprietary quaternary ammonium compound which acts as a bactericide) and 15 g per litre sucrose (Newman et al., 1998).

Pre-treatment with other products may only protect the flowers that are open on the stem at the time of treatment, and not flowers that open at a later date. Therefore, it would be necessary to have these products present throughout vase life to give any protection against ethylene exposure.



Note:

When using proprietary solutions, follow the manufacturer's or supplier's instructions. Trade names appearing in this publication have been used solely for ease of identification of the chemicals and not as an endorsement.


Reference Sources


Hicklenton, P.R., Newman, S.M., Davies, L.J. 1993. Night temperature, photosynthetic photon flux, and long days affect Gypsophila paniculata flowering. HortScience 28:888-890.

Hicklenton, P.R., Newman, S.M., Davies, L.J. 1993. Growth and flowering of Gypsophila paniculata L. 'Bristol Fairy' and 'Bridal Veil' in relation to temperature and photosynthetic photon flux. Scientia Horticulturae 53:319-331.

Newman, J.P., Dodge, L.L., Reid, M.S. 1998. Evaluation of inhibitors for postharvest treatment of Gypsophila paniculata L. HortTechnology 8:58-63.

Further reading:


  • Read national and international floricultural magazines.

  • Browse the internet and intraweb for information.

  • Contact a technical library such as a Crown Research Institute library.

Acknowledgements


P. J. Batt (former Horticultural Advisory Officer, MAF, Christchurch) for preparation of the original publication, and Ken Young (Agricultural Development Systems, Drury) for editing of the revision.

Prepared for HortNET - November 1998

While every care has been taken when preparing this document, no liability will be accepted by The Horticulture and Food Research Institute of New Zealand Limited for any loss or damage suffered as a result of applying the information contained in this document.


Copyright © 1998 The Horticulture and Food Research Institute of New Zealand Ltd. All rights reserved. Reproduction in whole or in part in any form or medium without express written permission of The Horticulture and Food Research Institute of New Zealand Ltd is prohibited.


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