Vegetable production in South East Queensland

In southern Queensland the major vegetable producing regions are the Lockyer and Fassifern Valleys, the Eastern Darling Downs and the Granite Belt (Table 1). Major crops include broccoli, lettuce, tomatoes, onions, pumpkins, sweet corn and potatoes. A wide range of other vegetables are also produced including cabbage, celery, Asian vegetables, cauliflowers, beans and capsicums.

Table 1: Area (Ha) and production (tonnes) for major vegetable crops in southern Queensland and Queensland (2011/12)

Crop

Border rivers (including Granite belt)

Condamine (including Eastern Darling Downs)

SEQ (including Lockyer and Fassifern Valleys)

Queensland

Total

 

Ha

Tonnes

Ha

Tonnes

Ha

Tonnes

Ha

Tonnes

Broccoli

289

1 833

126

958

1 152

7 339

1 591

10 143

Capsicum

147

3 975

1.3

2.6

16.2

280

1 335

25 077

Carrots

9

400

52

2 616

880

30 590

955

34 355

Lettuce

676

4 502

437

8 317

754

21 408

2 003

35 546

Potatoes

  

95

1 716

857

23 982

3 153

90 907

Mushrooms

3.1

1 200

  

12

4 694

15.8

6 158

Tomatoes

68

4 428

  

104

6 263

2 681

83 119

Onions

99

 

223

10 478

559

19 114

992

33 811

Other

1 748

 

392

 

6 872

 

19 338

 

ABS.gov.au. 2014. 7121.0 - Agricultural Commodities, Australia, 2011-12. [online] Available at: http://www.abs.gov.au/AUSSTATS/abs@.nsf/DetailsPage/7121.02011-12?OpenDocument [Accessed: 15 Apr 2014].

Soils and topography

The major soil types used for vegetable production vary from district to district.

Alluvial clay loams

Black alluvial clays and clay loams are the most productive soils in the Lockyer and Fassifern valleys, and consist predominantly of montmorillonite clay. In their native state, they are highly fertile and have neutral to slightly alkaline pH. Under continual cropping, responses to additional fertiliser (particularly nitrogen and potassium) can be expected.

The soils associated with the upper catchment tributaries and the levee banks of the Lockyer Creek are generally well drained with a loamy texture. Other alluvial soils of the region are generally heavier and not as well drained. Almost all the black alluvial soils in the region are suitable for irrigation and vegetable production.

In the Fassifern valley, production has also developed on small patches of Brigalow scrub soils (grey clays) and extended into some other marginal soils. Production areas in the Lockyer and Fassifern valleys are on flat, slightly sloping and undulating soils along the major streams and their tributaries. Some areas are subject to sporadic flooding. 

Krasnozems

Traditionally, the krasnozems of the Toowoomba range area grew vegetable crops but there is almost no farming there now due to urban encroachment. Potatoes are the main crop grown on the krasnozems in the mountains surrounding Killarney and extending to the Acacia plateau in NSW. These soils are generally deep, well-drained red clay loams of predominantly kaolinite clay, and oxides and hydroxides of iron and aluminium.

In their native state, they are highly fertile, both chemically and structurally. However, under continual cropping, this fertility is rapidly run down and, hence, they are generally of lower nutritional fertility than the black alluvial clays. Krasnozems are acidic and generally require lime and fertiliser for intensive vegetable production. After a few years of intensive farming it is important to add organic matter to improve nutrient availability (particularly phosphorus) and buffer against increased acidity (low pH).

The red soil areas on the Killarney range are at relatively high elevation, so they have milder summers than the Lockyer and Fassifern valleys. 

Eastern Darling Downs soils

The eastern Darling Downs contains a wide variety of soil types with different characteristics. For example, the Purrawannda dark medium clays are fertile and well drained.

Grey to brown alluvial cracking clays also exist in large areas of the eastern Darling Downs and where irrigation water is available these soils have been cropped intensively to vegetables. These clays are generally fertile and alkaline but vegetables grown on them do respond to fertiliser application.

The areas used for vegetable growing are mostly on slightly sloping land previously used for grain crops. There has been a period of industry expansion over recent years with the eastern Darling Downs becoming a significant summer vegetable production area. Lettuce ( mini, cos and iceberg ), celery and brassicas are the main summer vegetable crops, while cauliflowers are the dominant winter vegetable. 

Stanthorpe

In the Stanthorpe region, soils used for vegetable production are predominantly very well-drained granitic soils. The soils tend to be acidic, and have very low water-holding and cation exchange capacity. Therefore, inputs of lime, fertiliser and organic matter are required to resolve soil fertility problems. The region is elevated, allowing summer production of temperate vegetables.  

Soil problems

All these districts have extensive areas of soil that either have particular management problems restricting production or are totally unsuitable for vegetable production.

Even the most fertile alluvial soils of the Lockyer Valley can present management problems. Surface crusting after rain or irrigation hampers seed germination and restricts aeration. Heavy clay soils restrict access when wet and stay wet for extended periods. In the Fassifern Valley, some of the heavy clay soils are poorly drained, and cultivated hillsides can be infertile and prone to erosion. The areas of shallow red clay soils of the Killarney range have limited soil depth and are prone to erosion and compaction.

The wide range of soil types on the eastern Darling Downs each have their own management problems. For example, heavy self-mulching clays present germination problems. Successful farmers accurately match soil type, irrigation method and crop choice.

Large areas of ridge and scrub soils generally have very low fertility, frequently present drainage problems and lack available irrigation water. These soils are generally not suitable for commercial production. The publication 'Buying the farm for horticulture' offers practical step-by-step instructions on assessing soils for their suitability for horticultural production. 

Climate

Climatic variations exist across the four districts but the general pattern is described in Table 2. 

Table 32. Climatic data for sites associated with the Lockyer and Fassifern valleys, eastern Darling Downs and Toowoomba range regions
Centre Average annual
rainfall (mm)
January mean
max. (°C)
July mean
min. (°C)
Amberley 854 31.1 5.4
Applethorpe 784 26.4 2.0
Boonah 866 NA NA
Cambooya 726 30.1 1.9
Dalby 643 32.4 4.0
Gatton 791 31.6 6.2
Killarney 744 29.5 2.1
Pittsworth 698 30.0 5.0
Toowoomba 950 27.6 5.3
Warwick 710 30.0 2.6

Rainfall

Rainfall is distributed unevenly throughout the year, with up to 60 per cent falling during the summer months (December to March). The spring months of August and September are often the driest. The total rainfall varies from 1000 mm in the eastern districts to 650 mm in western districts, generally decreasing inland except for higher rainfall caused by the Great Dividing Range.

Temperature

Temperature extremes range from severe winter frosts (-10°C) to summer heatwave conditions (>40°C) in various locations across the region.

Summer maximum temperatures are modified by coastal influences in eastern districts and the altitude of the Great Dividing Range at Stanthorpe and Killarney. High summer temperatures with occasional heatwaves occur on the eastern Darling Downs. The maximum summer temperatures experienced in the lowland areas of the Lockyer and Fassifern valleys are generally in the mid to high thirties.

Winter minimum temperatures vary from near frosting to severe frosting (-10°C) on the eastern Darling Downs and Stanthorpe. No areas are completely frost free, though some areas experience no frosts in some years. The major vegetable growing areas of the Lockyer and Fassifern valleys experience, on average, one to three light frosts (-1°C) most years. Areas of the eastern Darling Downs and Stanthorpe experience 20-30 frosts, some of which are severe.

Market timing for domestic markets

The method of vegetable supply to the domestic market has changed. Increasingly, larger volumes of vegetables produced in South East Queensland are marketed directly to chain stores and large supermarkets. Some produce is still marketed through Brisbane, Sydney and Melbourne wholesale markets, with some going to Adelaide and Perth. The markets now demand quality assurance systems that guarantee a consistent supply of market quality product. For some commodities, a contracted grower supplies as an approved supplier to a quality assured packing shed for direct supply to a supermarket outlet.

South East Queensland is able to supply a wide variety of vegetables to appropriate markets throughout the year. This ability is highlighted by the production timing chart for the Lockyer Valley (Table 3). The highest returns are offered when market supply is possible at times when other production areas can not satisfy the demand. 

Table 3. Planting and supply timelines for vegetables grown in the Lockyer Valley

 

 

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Beans

Plant

x

x

x

x

x

x

x

        

x

x

x

x

x

x

x

x

x

Harvest

x

x

x

x

x

x

x

x

x

x

x

         

x

x

x

x

Beetroot

Plant

   

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

     

Harvest

        

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

Broccoli

Plant

   

x

x

x

x

x

x

x

x

x

x

x

          

Harvest

      

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

   

Cabbage

Plant

    

x

x

x

x

x

x

x

x

x

x

          

Harvest

         

x

x

x

x

x

x

x

x

x

x

x

x

   

Capsicum

Plant

x

x

              

x

x

x

x

x

x

x

x

Harvest

x

x

x

x

x

x

x

x

              

x

x

Carrots

Plant

     

x

x

x

x

x

x

x

x

           

Harvest

            

x

x

x

x

x

x

x

x

x

x

  

Cauliflower

Plant

    

x

x

x

x

x

x

x

x

x

x

          

Harvest

         

x

x

x

x

x

x

x

x

x

x

     

Celery

Plant

    

x

x

x

x

x

x

x

x

x

x

          

Harvest

        

x

x

x

x

x

x

x

x

x

x

x

x

    

Chinese cabbage

Plant

    

x

x

x

x

x

x

x

x

x

x

          

Harvest

        

x

x

x

x

x

x

x

x

x

x

x

x

    

Garlic

Plant

     

x

x

x

x

x

              

Harvest

                 

x

x

x

x

x

  

Lettuce

Plant

    

x

x

x

x

x

x

x

x

x

x

          

Harvest

       

x

x

x

x

x

x

x

x

x

x

x

x

x

    

Onion

Plant

     

x

x

x

x

x

x

             

Harvest

               

x

x

x

x

x

x

x

x

 

Potato

Plant

   

x

x

x

     

x

x

x

x

         

Harvest

         

x

x

x

x

    

x

x

x

x

x

x

 

Pumpkin Jarrahdale

Plant

x

x

             

x

x

x

x

x

x

x

x

x

Harvest

x

x

      

x

x

x

x

           

x

Pumpkin Jap

Plant

x

x

               

x

x

x

x

x

x

x

Harvest

  

x

x

x

x

  

x

x

x

x

            

Sweet corn

Plant

x

x

x

x

x

x

x

x

x

      

x

x

x

x

x

x

x

x

x

Harvest

x

x

x

x

x

x

x

x

x

           

x

x

x

x

Tomato

Plant

x

x

              

x

x

x

x

x

x

x

x

Harvest

x

x

x

x

x

x

x

x

            

x

x

x

x

Sweetpotato

Plant

x

x

x

                

x

x

x

x

x

Harvest

   

x

x

x

x

x

x

x

x

x

x

           

Watermelon

Plant

x

x

x

              

x

x

x

x

x

x

x

Harvest

x

x

x

x

x

x

x

x

               

x

Market timing for export markets

Australian producers face competition on overseas markets from countries such as South Africa, USA, South-East Asia and Brazil. Markets need to be investigated and developed in a thoroughly professional manner.

The establishment of large volume, long-term export markets is considered to be the only option for the long-term stability of the Australian vegetable industry.

The major items of importance in export marketing are:

  • availability of
    • products
    • markets, particularly making use of seasonal advantages
  • reliability, including
    • regularity of supply
    • consistency of supply
  • performance, including
    • quality of product
    • packaging
    • meeting of deadlines
    • suitable pricing policies.

Successful exporters commit to supplying the export market regularly and reliably with a product that meets the export market specification. Export markets should not be viewed as dumping grounds for surplus production and supply commitments should be honoured regardless of domestic prices.

The South East Queensland region currently exports several crops, including broccoli, onion, Chinese cabbage, sweet corn and celery.

Success depends on supplying markets at periods when growing is most profitable (e.g. winter brassica production in the Lockyer rather than summer production). 

Production limitations

Markets

The key to long-term market profitability is being able to produce a highly marketable product and develop a successful marketing strategy.

With modern post-harvest handling and transportation, no major market in Australia is beyond the grower's reach. Proximity to the Brisbane wholesale markets no longer provides the advantage it has in past years. Growers in other vegetable growing areas from North Queensland, Victoria, New South Wales and even Western Australia compete directly with Lockyer Valley growers. 

Irrigation water supply

The major source of irrigation water throughout the Lockyer and Fassifern valleys, and Darling Downs areas is groundwater from alluvial aquifers. In the Stanthorpe region, surface runoff is collected in dams. Other water sources include direct pumping from streams, off stream storages and on-farm catchment dams.

Most vegetable crops need about 3-4 ML/ha of water. At times, the four production areas have low quantities of irrigation water. The water quality is generally suitable for vegetable production and using this water on local soils presents no major problems.

Groundwater in the Lockyer Valley comes from a series of localised alluvial aquifers which vary in their quality and quantity of supply. The Department of Natural Resources and Mines (DNRM) has determined that average annual water use exceeds safe annual recharge and is recognised as a stressed groundwater area. This means water shortages are likely to be a recurring problem. Some areas in the Valley and Darling Downs have been declared and regulated by DNRM with assistance from local water advisory committees. DNRM has recommended that the whole of the Lockyer region be a declared sub-artesian area. Saline waters in the area have been used effectively with careful crop selection and irrigation practices. Poor quality water has the potential to reduce crop growth and downgrade soil structure.

The Fassifern Valley is similar to the Lockyer in having a series of aquifers supplying water. Where water is available, it is generally of reasonable quality. 

Temperature

Temperature extremes are the major limitations to vegetable production in these four districts. High temperatures during the summer, combined with normal summer rainfall, restrict summer production of many vegetable crops. Production during late summer and autumn is less likely to be adversely affected by these weather conditions.

The eastern Darling Downs, Stanthorpe and Killarney regions have a milder summer because of their altitude, enabling the production of crops such as lettuce, celery, brassicas and potato over this period.

Occasional heatwaves on the eastern Darling Downs preclude summer production of most vegetables except in some of the highland areas on the eastern extremities of the Downs.

Low temperatures during the winter prevent frost-sensitive vegetables being produced in most parts of the four regions, except in very small areas that are well protected and have an extremely low risk of frost. The production season for most cold or frost sensitive crops ends with the onset of cold weather or frosts.

Extremely low temperatures on the eastern Darling Downs can limit growth and quality of some of the more cold tolerant vegetable crops. Mid-winter production in these areas is often risky for this reason.

Milder winter minimum temperatures in the Lockyer and Fassifern valleys enable high-quality, cold-tolerant crops to be produced in most years.

Long term averages for rainfall and temperature can be found at:

Seedling production

Many intensive vegetables are established in the field using containerised seedlings. Brassicas, tomatoes, lettuce, capsicums and celery are mainly established this way. Some broccoli and lettuce are direct-seeded using precision planters.

Vegetable seedling production is a specialised business, seedlings are usually produced by specialist contract seedling growers. A high level of expertise and experience is required to produce the high-quality seedlings that are needed in intensive horticulture.

Organic farming

Many vegetable consumers are interested in purchasing products that have not been grown using synthetic chemicals, particularly pesticides. Organic (biological, holistic, ecological or natural) farming is one method of providing this type of product.

Some fruit, vegetable and grain farmers in the region are using organic farming practices. Pest and disease pressure is normally very high in an intensive vegetable production district. However, as more soft option products (IPM compatible) become available to the vegetable industry, the pest management problems associated with organic farming will become more manageable.

Hydroponics

Some vegetable growers in the region have established specialised market outlets for certain hydroponically (soil-less) grown produce. However, many of the advantages often attributed to commercial hydroponic vegetable production do not apply in this region, which has the ideal natural environment for conventional production methods.

Hydroponic vegetable production normally demands a higher level of production technology than conventional cropping methods. A knowledge of how to grow a particular crop conventionally is a tremendous advantage to successful hydroponic culture. Establishment and running costs are higher, though a well designed system can save on labour.

Light and temperature control are critical if the hydroponic system is in a greenhouse. One advantage to green house production is the ability to minimise weather impacts – particularly rain damage and disease. However, few vegetable crops are naturally adapted to greenhouse cropping in the region. For example, hydroponic lettuce can be grown successfully in the open. So far, the only vegetables showing potential for successful commercial hydroponic production in this region are lettuce (in the open) and cucumbers (in a greenhouse).

Conventional control measures, especially hygiene, are required to combat the same pest and disease problems that affect field-grown crops. However, some natural predators can be used more effectively in an insect-proofed greenhouse than in the open.

Anyone interested in hydroponic culture is strongly urged to attend a course on hydroponics.

Future prospects

Commercial production of vegetables on farms in this region will continue into the future. Cropping types and patterns will change in response to changing markets, economic returns and management of resources, particularly water. There is little potential to expand production of vegetables for domestic markets. These markets are already well supplied for most of the year, and production above market demand very quickly leads to reduced prices.

Production to meet specific market demands will generally be profitable in the long term. Lucrative markets are very small and exist for very short periods each year.

An export market exists for some vegetables and the volume which could be marketed is many times larger than the Australian domestic market demands. A decision to produce for export must be considered seriously, carefully and purposefully. Any major expansion of vegetable production in the region would have to be aimed at the export market. Much greater vegetable production could potentially be achieved in the South East Queensland region but only for supply to an export market.

Further information

Last updated 15 April 2014