Producing biomass: Biomass types: Crops: Grain sorghum
In Australia, grain sorghum is primarily processed for livestock feed. It is also used as a feedstock for producing ethanol.

Benefits of growing grain sorghum

Grain sorghum usually produces a grain with higher starch content than sweet sorghum. This grain is predominantly used for animal feed but is also used as a feedstock for biofuel production.

Dalby Bio-Refinery in Queensland’s Darling Downs converts grain sorghum to ethanol. The biorefinery also produces a high protein animal feed (wet cake) and syrup from the ethanol process, which it sells to local dairies and feedlots.

Agronomic benefits

Sorghum is the main summer crop grown in Queensland and northern New South Wales. It plays a key role in providing feed grains to the beef, dairy, pig and poultry industries. It is also a good rotation crop that tolerates heat and moisture stress (Department of Agriculture, Fisheries and Forestry).

Sorghum is well suited for dry conditions, areas with uneven rainfall distribution, and high year to year variation in rainfall and water supplies.

Other advantages to growing sorghum include its:
  • ability to be grown on marginal soils
  • shorter growing season.
The lower variable cost of sorghum can help growers spread risk by:
  • producing another crop at lower cost
  • spreading limited capital across more acres.
Commercially grown sorghum varieties can be classified as either grain, sweet, or forage sorghum.

Evaluating the economics of growing grain sorghum

Grain sorghum production in Australia is set to expand as grain prices increase due to use of grain to produce ethanol around the world, according to Dr Peter Wylie, Horizon Rural Management, in his report, Managing sorghum for high yields: A Blueprint for doubling Sorghum production [PDF 399 kb].

Dr Wylie says that rising grain prices may limit ethanol production in Australia but, with improved agronomy and prices, sorghum production will become more attractive.

Managing sorghum for high yields [PDF, 1.2 MB], published by the Grains Research and Development Corporation (GRDC), claims that sorghum is the most profitable crop in the higher rainfall areas of the northern grain belt. It also states that it may be as profitable as wheat in western growing regions, if slightly more yield can be achieved to make up for a lower price.

If sorghum is used for ethanol production, the price premium for wheat over sorghum may decline further, making it more profitable than wheat in all dryland areas.

The costs associated with producing ethanol from sorghum are outlined in Ethanol Production from Grain [PDF 1.2 MB], published by the Western Australian Department of Agriculture.

The document states that ethanol mills buy grain for its starch. The higher the starch percentage content the higher the grain price that can be accommodated.

Sorghum grain typically contains more than 70% starch, the highest of the grain crops. 1 tonne of starch will produce about 620 litres of ethanol. This translates to:
  • 1 tonne of grain at 60% starch producing 360 litres of ethanol
  • 1 tonne of grain at 70% starch will produce 420 litres of ethanol.

Growing grain sorghum

Grain sorghum, both dryland and irrigated, is usually grown on heavy clay soils.

The Queensland Department of Agriculture, Fisheries and Forestry provides a guide to sorghum varieties and planting methods as well as comprehensive information on nutritional inputs and disease management.

The Department of Primary Industries NSW provides a similar fact sheet: Best management practices for grain sorghum [PDF 879 kb].

Although sorghum is not widely grown in Western Australia, the Department of Agriculture, WA, has a factsheet Sorghum growing for WA growers [PDF 42 kb].

Managing sorghum for high yields [PDF 1.2 MB], also offers growers best practice strategies for improving yields of grain sorghum.

The guide provides information on:
  • fallow management strategies
  • planting time and optimal row spacings
  • nutrition and fertiliser strategies
  • weed and pest control.

Harvesting grain sorghum

The Department of Agriculture, Fisheries and Forestry has information on Sorghum – nutrition, irrigation and harvest which covers:
  • when to harvest
  • header settings
  • pre-harvest spraying.

Supplying grain sorghum

Dalby Bio-Refinery Ltd processes about 500 tonnes of sorghum grain a day and about 200,000 tonnes a year. As such it requires a constant supply of sorghum grain throughout the year. Some of its suppliers store their grain on farm and sell small batches to the refinery through the year.

Best management practices for grain sorghum fact sheet [PDF 879 kb] (DPI NSW) stresses the importance of:
  • preventing moisture from getting into stored grain so that fungi doesn’t start to grow and spoil the grain
  • inspecting grain regularly to check for insects.


The Queensland Department of Agriculture, Fisheries and Forestry claims that most insect control methods for stored grain work against all species, so you don’t need to identify the storage pests to make decisions about most control methods. They also provide a guide on controlling insects in stored grain.

Contacts

Heather Bone

RebusJ Sustainability

50 Willowvale Drive, Willow Vale , Queensland 4209
Phone: 0400473733

heather.bone@hotmail.com
ADI Systems Ltd

ADI Systems

ADI Systems (Asia Pacific), 50 Yeo Street, Neutral Bay, NSW 2089
Phone: 1.800.751.806 (toll free)

asiapacific@adi.ca
Prof. Christopher Grof

University of Newcastle

Biological Sciences Callaghan, University Drive, Callaghan, NSW 2308
Phone: (02) 4921 5858

Chris.Grof@newcastle.edu.au
Andrew Borrell

Queensland Alliance for Agriculture & Food Innovation

Hermitage Research Facility, Warwick, Queensland,
Phone: 07 4660 3640

a.borrell@uq.edu.au
Colin Peace

Jumbuk Consulting P/L

PO Box 2252, HAWTHORN, VIC 3122
Phone: 0413 835 793

colin@jumbukag.com.au