Okra

24.05.17

Okra (Abelmoschus esculentus) is grown for its fibrous fruit with successful production in tropical and warm temperate regions around the world. It is known in many English-speaking countries as lady’s fingers, bhindi or gumbo. It is a member of the Malvaceae plant family, and therefore related to cotton, cocoa and hibiscus.

Overview

The species is cultivated as a short season, summer (or dry season) annual, growing to two metres tall. The plant has white to yellow flowers and long, lobed leaves. The fruit is a capsule up to 18cm long, containing numerous seeds.

Okra is a healthy food being high in fibre, vitamin C and folate; it is also high in antioxidants. It is usually consumed whole or sliced, and steamed or stir-fried. The fruit is high in mucilage and it can be used as a food thickener.

Okra is usually grown under drip or furrow irrigation and mulch may be used to improve water use. The harvesting of okra is very labour intensive as the product needs to be handled with care because it can bruise and blacken easily.

World okra production is 8.9 million tonnes and in the same period Australia averages 2,000 tonnes, mainly in the Northern Territory.

The okra industry in Australia is classified as an emerging industry and is covered by the industry association AUSVEG. In the Northern Territory, Asian vegetables, including okra, are also represented by the Northern Territory Farmers Association; and the Northern Territory Vietnamese Horticultural Association (NTVFA).

Facts and figures

  • Okra is a member of the mallow family and grows in tropical and warm temperate regions
  • Most of the production in Australia occurs in the Northern Territory
  • Okra is very labour intensive to harvest and is best marketed immediately
  • All Australian okra production is consumed domestically

Production status

World okra production has increased steadily over the past decade to reach 8.9 million tonnes in 2016. The main okra producing countries are India (62%), Nigeria (22%), Sudan (3%) and Mali (3%).

Most Australian okra is grown in the Northern Territory. All Northern Territory okra is sold on the domestic market, mainly to major city markets, including Sydney and Melbourne.

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Map of current and potential growing regions

Uses

Okra is a popular health food due to its high fibre, vitamin C, and folate content. Okra is known for being high in antioxidants, and it is also a good source of calcium and potassium.

The pods of the okra plant are consumed cooked, entire or cut up. They may also be dried and used in soups. Okra pods can also be canned, frozen or pickled in brine. The pods contain quite a lot of mucilage, which provides a high source of fibre but may also result in a gooey cooked product.

Greenish-yellow edible okra oil can be pressed from okra seeds; it has a pleasant taste and odour, and is high in unsaturated fats such as oleic acid and linoleic acid.

Production Requirements

Growing regions

Most okra produced in Australia was grown in the Northern Territory with some production in south eastern Queensland during the Northern Territory wet season.

Soil type

Okra can be grown in many types of soil but is best suited to irrigated, well-drained, sandy loam soil, and a pH of 6.0–6.8(water).

Climate

Tropical and warm temperate climates are suitable for okra production. Optimum temperature for germination is 35°C, but will still occur at 15°C. Okra does not tolerate frosts.

Most cultivars need a short day length to initiate flowering, but there are long day and day neutral cultivars. Day neutral cultivars will continue flowering from flower initiation until the first frost. The plant is tolerant to water stress but yields will be reduced, particularly if stress occurs during flowering or pod filling stages. Low levels of rainfall and humidity are preferable for seed production.

Varieties

Okra seed, both hybrid and open pollinated, is available from commercial seed suppliers. The most popular varieties are Clemson Spineless and dark green.

Planting and crop management

Growing sites for okra should be clean and free from sticks, and the soil should be well drained. Okra is best planted when soil temperatures are 20–35°C. In the Northern Territory okra is usually planted from April to June. Okra plants are susceptible to wind damage and it may be necessary to establish windbreaks every 50 metres.

An appropriate fertiliser or nutrition program should be followed to match anticipated yields. For example, in the Northern Territory, growers fertigate with soluble NPK, a fertiliser containing nitrogen, phosphorous and potassium, as well as trace elements throughout the growing season.

Other fertilisers used include MKP (a soluble fertiliser containing potassium and phosphorous), calcium nitrate and potassium nitrate. Side dressing during crop growth should also be considered.

Okra yields can be increased through the use of mulch; the most successful being a combination of a green manure crop and plastic mulch. The most effective form of irrigation to use with plastic mulch is drip irrigation.

For more general information on growing vegetables in the semi-arid tropics of the Northern Territory refer to the Northern Territory Vegetable Growers Guide.

Weeds, pests and diseases

Good weed control should be undertaken before planting okra, and a green manure crop may aid in this purpose as well as provide nutrients for the okra crop. Few herbicides are registered for use on okra and relevant advice should be sought from local departments of agriculture.

The most common disease affecting the okra plant is verticillium wilt, often causing a yellowing and wilting of the leaves. Other diseases include powdery mildew in dry tropical regions and leaf spots. An appropriate crop rotation should be followed and okra, eggplant and tomatoes should not be planted in the same field more than once every four years, to prevent build-up of disease pathogens.

Okra is susceptible to damage by nematodes, especially the tropical root-knot nematodes Meloidogyne haplaand Meloidogyne javanica. Similar for disease pathogens, a crop rotation should include crop species that are not susceptible to nematodes, to prevent a build-up of nematode populations in the soil.

Pests of okra include caterpillars (especially Spodoptora litura), aphids, white fly and termites.

For more general information on growing vegetables in the semi-arid tropics of the Northern Territory refer to the NT Vegetable Growers Guide.

Infrastructure Requirements

Standard horticultural equipment can be used to produce okra including a tractor, a bed former, irrigation and spray equipment. Washing, cooling and storage facilities are required for post-harvest processing and storage.

Harvesting & Processing

Okra develops quite quickly with the first pods being harvested 4–5 weeks after seedlings are planted. The pods should be picked within a week of flowers opening and being pollinated — at about 5–8cm long — and they need to be picked daily in the Northern Territory during warm weather or every two to three days during the cooler dry season. Pods become tough and inedible if left too long.

Black spot may be an issue post-harvest and pods should be treated with a post-harvest wash in a 100ppm chlorine bleach solution before packaging.

Okra pods should be handled with gloves as they are susceptible to bruising and if this occurs, they will blacken rapidly. They should be packed in waxed cartons and stored in bags at 7–10°C at a humidity of 90–95%, but ideally they are marketed immediately after harvesting. Okra should not be stored with melons, bananas or mangoes as these species give off ethylene gas which will accelerate the ripening of okra.

Markets & Marketing

All okra produced in Australia is consumed on the domestic market, mainly in the southern states. It is mostly marketed through the vegetable markets in Sydney. Transport costs to these markets can be significant.

Risks & Regulations

Risks/challenges

Although okra is a high turn-over crop, its production is particularly labour intensive and requires certain skills for harvesting. The pods bruise and blacken easily and must be handled with care. The product is also highly perishable and requires a tightly-managed supply chain to market.

Regulatory considerations

Some producers of Asian vegetables choose to participate in Freshcare, which is currently the largest Australian on–farm assurance program for fresh produce for on-farm food safety and quality and environmental certification services.

If processing raw product into value-added food products, consideration should be given to food standards regulations. Further information can be found at the websites of FreshcareHACCP and Food Standards Australia New Zealand.

Publications

Publications/information

Emerging animal and plant industries: Their value to Australia RIRDC report (2014)

Taking Stock of the Australian Asian Vegetables Industry RIRDC publication (2011)

Okra Growing Note VG2  Northern Territory Department of Primary Industry, Fisheries and Mines (2004)

Asian Vegetable Industry – A situation assessment RIRDC publication (2003)

Vegetable Growers Manual Northern Territory Department of Primary Industry, Fisheries and Mines publication (2012)

Other resources

Freshcare is an industry owned, not-for-profit on-farm assurance program, established and maintained to service the Australian fresh produce industry.

HACCP Australia is a leading food science organisation specialising in the HACCP Food Safety Methodology and its applications within the food and related non-food industries.

Food Standards Australia New Zealand is a bi-national Government agency. They develop and administer the Australia New Zealand Food Standards Code, which lists requirements for foods such as additives, food safety, labelling and GM foods. Enforcement and interpretation of the Code is the responsibility of state and territory departments and food agencies within Australia and New Zealand.

Industry Bodies

AUSVEG is the national peak industry body representing the interests of Australian vegetable and potato growers and is committed to securing the industry’s future.

Northern Territory Farmers Association – is the peak body for plant industry in the Northern Territory

Northern Territory Vietnamese Horticulturalist Association

Image Gallery

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Okra under irrigation

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Raw okra

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Okra plant with growing okra

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Harvested and packaged okra