Irrigated maize builds business resilience
GroundCover™ Issue: 106 | Author: Nicole Baxter
Fourth-generation grain grower Campbell Dalton introduced irrigated maize to his family’s mixed-farming system to help build business resilience.
While rice is an excellent earner, Campbell says maize grown in a row-crop arrangement on his family’s farm near Yenda, east of Griffith in south-west New South Wales, has a lower water requirement (9.5 megalitres per hectare for maize versus 11ML/ha for rice).The 26-year-old decided to trial maize across 80ha of his family’s 5000ha mixed farm in the Riverina region three years ago when he returned after working as a grain trader.
But learning how to grow and manage a new cereal crop was not without its challenges. One of the biggest challenges was the earthworks required to change the trial paddock from a flat, compacted pasture to a soft seedbed with beds and furrows and a siphon-fed furrow irrigation installation.
“I was lucky to have good neighbours and agronomists who would come in and say ‘nup, do it again’ until we got it right,” Campbell says.
To keep costs low in the first year, most of the equipment needed for establishing and managing the crop was borrowed. However, Campbell would not encourage other growers to follow his example. “It nearly gave me a stroke,” he quips. He has subsequently bought his own machinery.
To prepare for sowing, the trial paddock was deep-ripped twice, spread with gypsum and processed cow manure, and then fallowed with a disc plough.
Next, beds or hills (spaced 914 millimetres apart) were formed, knockdown herbicides applied and 500 kilograms/ha of diammonium phosphate and urea was drilled to a depth of 254mm.
The beds were then shaped and rolled to produce a fine seedbed before 80,000 seeds/ha were planted in October with the aim of producing more than 70,000 plants/ha.
After sowing, pre-emergent and post-emergent herbicides were applied targeting grass and broadleaf weeds.
Campbell says another challenge was infrastructure. With pipes and pumps designed for rice (requiring 5 to 15ML/day), their equipment was put under significant pressure to deliver the 30 to 40ML/day required to water the maize crop.
Although small problems seemed like big problems to Campbell that year because everything was new, he says his neighbours and agronomists provided “fantastic support”.
Then, when the crop appeared to be progressing well, torrential rain in March 2012 flooded 90 per cent of the farm three weeks before harvest.
The floodwater came within about 50mm of the maize heads, delaying harvest for five weeks. Fortunately, the crop had not matured. “We were exceptionally lucky,” he says.
Campbell harvested the crop at 15.5 per cent moisture and dried it twice – first to 14.5 per cent and again to 14 per cent – before delivery.
“It was a long and painful process at five tonnes per hour,” he says. “But it was well worth the effort. We were scrupulous with hairline cracks and fractures, and as a result there were no problems with quality.”
He encourages those considering growing maize in the south to budget for drying grain once every three years.
After analysing the results, Campbell was pleased with his first season’s work. The 80ha of maize yielded 13.5t/ha on average and produced a healthy return on investment.
Although his second attempt at growing maize was easier because of the experience he had gained, the hot 2013 summer meant the crop had to be irrigated from the second week in November to the last week in February.
“It was the only reason we managed to get through,” Campbell says.
Yields for the 2012-13 feed maize were 14t/ha, which outperformed the grit maize at 12t/ha.
To reduce costs, Campbell has this year switched from siphon-fed irrigation to bankless channel irrigation to improve labour efficiency.
The new system comprises a sequence of terraced bays with a 150mm drop in each terrace which, although watered separately, are linked by a bankless channel (Figure 1).
Each bay is irrigated by backing up water behind a closed check gate in the head ditch, causing water to spill into the adjacent bay and travel along furrows that run perpendicular to the bankless irrigation channel.
After the first bay has been irrigated, a check gate is opened to allow water to flow into the second bay. The process is repeated until all the bays in the sequence are watered.
Campbell says the main advantage of the bankless channel irrigation system is not having to change up to 600 siphons every 12 hours.
What previously took Campbell six hours a day to complete for five months of the year now takes one of his employees 15 minutes a day when crops are being irrigated. This change has released Campbell to work on other aspects of the business.
With 200ha (or 12 per cent) of his irrigated land done, the remaining area will be converted when finances allow. Campbell says it will be worth the effort because it provides the flexibility to swing into cotton if prices are high.
Going forward, Campbell’s most immediate focus is on striving for excellence in all that he does and working to further improve business efficiency.To do this, he is implementing 2.5-centimetre GPS precision guidance, analysing the optimum times to buy and sell farm commodities, and tweaking the business to ensure capital and human resources are working at maximum capacity.
More information:Campbell Dalton,
0408 637 003,
GRDC Project Code GCS10574
Region South, North, West