Chinese broccoli

This web page was produced by the Centre for Plant and Water Science of CQUniversity, and funded by RIRDC.

WARNING: The information on this page has been gathered from both published and unpublished material, and contains comments and opinions from people working in the field. CQUniversity cannot guarantee all the information, and we stress that it is necessary to CHECK WITH THE SOURCE of the information, before using it to make a business decision. Please read our disclaimer.

Species: Brassica oleracea L. cv. group Chinese Kale

Family: Cruciferae

Crop status: New

Varieties

Different varieties vary in stem length and colour, from light to medium green (Cantwell et al. 1996). The F1 hybrid varieties generally grow more vigorously (Moore and Morgan 1998). Varieties that are re-sown annually by Victorian producers have an excellent flavour, and are highly competitive with commercial varieties. Vong Nguyen (NSW) has studied varieties in previous years. See Seedquest for a list of seed companies.

Agronomic trials

Trials in 1999 are being conducted throughout Victoria (Agriculture Victoria), at Burnie, Tasmania (Frank Hay) and at Gatton, Queensland (Alan Wearing). Observation trials have also been held at Burringbar, via Murwillumbah (Peter McLaughlin 1998, pers. comm.).

Production

Grown commercially in NSW, WA, NT, Qld and Vic (Lee 1995). Victorian production in 1990/91 totalled 22.8 t from 7.1 ha (Waters et al. 1992).

Soil type: Kailaan requires a fertile soil with good drainage and a high level of organic matter (Moore and Morgan 1998).

pH: Prefers between 6.0 and 7.0. Do not let it fall below 5.0 (Moore and Morgan 1998).

Climate: Kailaan is a cool season crop with some frost tolerance. It can be grown year round in the tropics (Sagwansupyakorn 1994) and in Victoria, but the optimum variety varies during the season (Moore and Morgan 1998). Uniform conditions are favourable: not too wet, dry or shady, and not too windy when the plant is young (Moore and Morgan 1998). It is a perennial that is usually grown commercially as an annual (Sagwansupyakorn 1994).

Temperature: Optimum temperature is 18-28ºC for rapid growth. Low temperatures promote early flowering and are necessary for complete floral development. It is frost tolerant and more heat tolerant than other broccoli (Sagwansupyakorn 1994).

Mixed cropping: Chinese mustard and Chinese broccoli can be used as a bait crop for daimondback moth (Yu et al. 1998).

Germination: Optimum temperatures for germination are 25-30ºC (Sagwansupyakorn 1994).

Seed size: Approximately 200 seeds/g.

Sowing depth: 0.6 cm (Moore and Morgan 1998).

Plant density: 2-4 rows/bed and 8-12 cm between plants, for a density of 108 000 to 220 000 plants/ha (Cantwell et al. 1996). Sow heavily and then thin after 3 weeks of growth. Thinned plants can be sold as the first harvest (Sagwansupyakorn 1994). A high density slows down the maturation process, raises the leaf area index and produces a more desirable product and higher marketable yield. A spacing of 10 cm, however, causes a reduction in mineral content due to competition among plants for nutrients (Moore and Morgan 1998).

Days to emergence: 3-6 days in summer and 4-10 days in autumn (Moore and Morgan 1998).

Transplants: Transplant at 3-4 weeks (Moore and Morgan 1998). Growth rates from seedling trays in polyhouses are often too fast, particularly in warm weather, causing early flowering and minimal vegetative production. Seedling trays require wind protection but should only be stored in polyhouses in cool weather.

Fertiliser: A number of fertiliser regimes are discussed in Moore and Morgan (1998). Base dressing of 500 kg/ha Pivot 800, side dressing of 125 kg/ha CaNO3 or equivalent at 4 weeks after emergence (3 weeks after transplanting). Dual (metalochlor) at 3 l/ha applied directly after transplanting.

Watering: Requires frequent light watering for optimum growth, since it is shallow rooted (Moore and Morgan 1998).

Time to harvest: 10 weeks from sowing in autumn and 8-9 weeks in summer (Moore and Morgan 1998).

Harvest: Young flowering stems are selected with compact florets and small leaves attached, and cut at 15 to 20 cm length (Anonymous 1997) with a sharp knife. Flavour is maximised when plants are harvested well before the buds begin to open. They should be harvested frequently to prevent bolting and toughening, particularly in summer. About three cuts can be obtained from one stem, and the main stalk should be cut relatively short to enhance further growth. A liquid feed after harvest may benefit regrowth (Moore and Morgan 1998).

Yield: Victorian yields in 1990/91 averaged 3.2 t/ha (Waters et al. 1992). Average yield in a season with 2-3 harvests is 6-11 t/ha (Shuler 1995). Yield depends on harvesting frequency and method (Sagwansupyakorn 1994).

Postharvest

Handling: Harvested in the early morning to minimise water stress, and tied into bunches of 5 to 7 plants. The main stem should be 10 - 15 cm and 1.5 - 2.0 cm wide at the base (Moore and Morgan 1998). Common postharvest defects include open or deteriorating flowers, yellowed or decayed leaves (Cantwell et al. 1996)

Storage temperature: 0-5ºC (Cantwell et al. 1996). Best at 0-1ºC but should not be allowed to freeze (Thomson 1999).

Relative humidity: 90-95%. Highly susceptible to water loss (Cantwell et al. 1996)

Shelf life: A shelf life of more than 21 days is possible at temperatures close to 0ºC, but at 5-10ºC it is reduced to 7-14 days (Zong et al. 1998).

Ethylene: Exposure to 1 ppm ethylene reduced shelf life by 30% at 5ºC (Zong et al. 1998).

Pests and diseases

Diseases identified in Victoria include Alternaria, causing lesions on the leaves, and Peronospora parasitica (Downy mildew) and Puccinia cymbopogonis, causing spotting on the leaves (Chew and Morgan 1997, Moore and Morgan 1998).

Aphids, green looper caterpillar and white butterfly caterpillar are the common pests. White rust (Albugo candida) causes a mass of small white, circular raised spots on both sides of the leaf, and is common in cool, wet weather (Nguyen 1992).

Diamondback moth prefers Chinese mustard and Chinese broccoli over other Brassica crops (Yu et al. 1998).

Potential viruses are listed at Plant viruses online (Brunt et al. 1996).

(A)

(B)

Figure 1: High and low prices (A) and throughput (B) of kailaan at Flemington Markets during 1996 (green), 1997 (blue) and the first half of 1998 (red). Note that the weight of one dozen cuttings can vary with season (Flemington Market Reporting Service, NSW Agriculture).

Quality assessment

15-20 cm tall green stalk and white flower buds developed but not open (Cantwell et al. 1996).

Domestic markets

Kailaan is one of the most popular Asian vegetables in Australia. It is eaten boiled, steamed or fried (Anonymous 1997). Development potential was rated as high for the fresh and processed domestic markets. Ethnic restaurants and small retailers are well supplied, but recent interest from supermarket chains has created a new domestic outlet (Vinning 1995). It was rated a priority Asian vegetable for developing a domestic fresh market by workshop members reported in Lee (1996).

Kailaan is available throughout the year in Asian grocery stores of Sydney and Melbourne. Prices at Melbourne Markets average $0.90 to $1.50/bunch wholesale, while retail prices are $1.00 to $1.60/bunch (Moore and Morgan 1998). Melbourne is supplied by both Victoria and New South Wales (Chew and Morgan 1996).

Export markets

(click here for exchange rates).

The main market is to Chinese communities (Vinning 1995). There have been mixed reports about the potential for exports. It appears that markets are relatively easy to find, but shipping costs are high due to the low density value of the product.

Singapore prices have been in steady decline, reaching about S$3.00/kg in 1994. Prices tend to peak from April to June (Vinning 1995).

Taiwan. Three varieties are marketed: Pugong, Helgelan and Gelanya, totalling about 4 200 t/year. Helgelan is produced at much greater quantity but Gelanya prices are higher, usually double (1993 data). Prices are highest in June - July and November - December, reaching NT$20 - 40/kg (Vinning 1995).

Thailand produced about 145 000 t in 1994. Retail prices have steadily increased, reaching 14 Baht/kg in 1993. Prices are higher in the second half of the year, particularly October and November (Vinning 1995).

Figure 2: Taiwanese imports of fresh or chilled kale and similar brassicas 1997. This material provided courtesy of the Asia Regional Agribusiness Project/Fintrac Inc. through the Market Asia web site at http://www.marketasia.org.

Related projects

Kiang Lee, Henderson Seed Group (Duration?). Varietal improvement of the Asian Vegetable 'Kailaan' and production of a kailaan broccoli hybrid. HRDC Project Number?

References

Anonymous (1997). Using the popular Asian greens. Good Fruit and Vegetables (April): 22.

Brunt, A.A., Crabtree, K., Dallwitz, M.J., Gibbs, A.J., Watson, L. and Zurcher, E.J. (eds.) (1996 onwards). `Plant Viruses Online: Descriptions and Lists from the VIDE Database. Version: 16th January 1997.'

Cantwell, M., X. Nie, R. J. Zong and M. Yamaguchi (1996). Asian vegetables: Selected fruit and leafy types. Progress in new crops. Ed.: Janick, J. Arlington, VA, ASHS Press: 488-495.

Chew, M. and W. Morgan (1996). Melbourne retail Asian vegetable survey. Melbourne, Agriculture Victoria 143 pp.

Chew, M. and Morgan, W. (1997). List of identified pests and diseases affecting Asian vegetables. Access to Asian Vegetables. (2): 1

Lee, B. (1995). Audit of the Australian Asian vegetables industry. RIRDC Research Paper No. 95/13. Canberra, Rural Industries Research and Development Corporation 97 pp.

Lee , B. (1996). Assessment of economic benefits for Asian vegetables. RIRDC project CON-4A review meeting 14 November 1996.

Moore, S. and W. Morgan (1998). Chinese broccoli. The New Rural Industries. Ed.: K. W. Hyde. Canberra, Rural Industries Research and Development Corporation: 163-165.

Nguyen, V. Q. (1992). Growing Asian vegetables. Agfact, NSW Agriculture H8.1.37.

Shuler, K. D. (1995). Guidelines for Chinese leafy and root crop vegetable production in South Florida. In: FACTS 1995 Vegetable Crop Proc. Ed.: G. J. Hochmuth and D. N. Maynard: 53-57.

Sagwansupyakorn (1994). Brassica oleracea L. cv. Group Chinese Kale. In: Plant Resources of South-East Asia: Vegetables. (Ed; Siemonsma, J. S. and K. Piluek). Wageningen, The Netherlands, Pudoc Scientific Publishers 115-117.

Thomson, G. (1999). Postharvest handling of leafy Asian vegetables. Access to Asian Vegetables. (16): 1.

Vinning, G. (1995). Market Compendium of Asian Vegetables. RIRDC Research Paper No. 95/12. Canberra, Rural Industries Research and Development Corporation 386 pp.

Waters, C. T., Morgan, W. C. and McGeary, D. J. (1992). How to identify, grow and use oriental vegetables. Melbourne, Agmedia 128 pp.

Yu, G. Q., Wu, W. J., Gu, D. J. and Zhang, W. Q. (1998). Preliminary studies on oviposition preference to host plants of diamondback moth, Plutella xylostella and its application. [Chinese]. Journal of South China Agricultural University 19(1): 61-64.

Zong, R. J. (1992). Postharvest studies on four fruit-type Chinese vegetables. Acta Horticulturae 318: 345-354.

Zong, R. J., Morris, L. L., Ahrens, M. J., Rubatzky, V. and Cantwell, M. I. (1998). Postharvest physiology and quality of gai-lan (Brassica oleracea var. alboglabra) and choi-sum (Brassica rapa subsp. parachinensis). Acta Horticulturae No(467): 349-356.