Last year, in what was a very challenging season, the Lewingtons of Uranquinty, in the Riverina, grew a two-tonne-per-hectare canola crop.
Derek Lewington, who farms with his wife Skye and parents Lou and Jenny, said he put the yield nearly entirely down to the residual moisture left by the field peas they grew the year before.
"In a terrible year it was a really good result," Mr Lewington said.
"The field peas don't use all the moisture deep in the profile so we find the following canola crop usually has left over moisture to use."
The Lewingtons have been growing field peas for more than 20 years and it has become a crucial part of their four-year rotation of wheat, barley, field peas and canola.
As well as retaining moisture, the peas also help with nitrogen fixation and weed control.
"It's a double break with the field peas and canola for grass weed control," Mr Lewington said.
"We use double knocking to guard against Roundup resistance. The field peas are not sown until the end of May so that allows for good weed control.
"It gives us a different mode of chemical control on the rye grass by using Select and Factor on the field peas. If there's resistance to Select, Factor should fix that up."
Mr Lewington said he thought they got at least a two-year benefit out of the nitrogen fixed by the field peas.
"It definitely reduces our inputs, for example the 2t/ha canola crop we grew last year only had 80kg of urea per hectare on it, 40 units of N," he said.
But field peas are not without their challenges.
"They can be a pain to harvest because they go flat on the ground sometimes and you've got to scrape them up off the dirt.
"We pull a rubber tyre roller behind the seeder to crush the clods down and even the ground out. That helps with harvest, so we're not pulling dirt into the header front."
He said pests like pea weevil and heliothis could be a problem.
"We do a barrier spray of insecticide around the paddock in spring, that usually protects us against pea weevils getting in."
While, bacterial blight could also impact yield.
"For quite a while now we've been using the variety Percy Peas, they're meant to be reasonably resistant to bacterial blight," he said.
"But in certain years we do have quite a lot of problems with blight, we've had big dead areas which really hurts your yield."
This year's field pea crops have just emerged after a May 25 sowing date.
"They look really good so far, but there's a while to go."
Retaining quality is key for marketing peas
The benefits of field peas to the overall rotation are clear, the pulse offering moisture retention, nitrogen fixation and can be used as a valuable weed break.
But, can you make money from field peas themselves?
The Lewingtons said in a good year they yielded three tonnes per hectare, while the average yield was between 1.5t/ha and 2t/ha.
"They're not always the best gross margin," Mr Lewington said.
"In the good years when the price is high, they can be right up there with the other crops, but they usually are a little bit behind.
"We'll take that sacrifice for the benefit it gives to the rest of our rotation."
He said they used to sell field peas for human consumption, exporting to India.
But since the 50 per cent tariff was put in place in November 2017, that premium had disappeared.
"In the domestic market it depends on the feed demand, our price range is anything from $550/t to $250/t," Mr Lewington said.
"We store them at harvest and sell them throughout the year."
Mr Lewington said retaining quality was crucial for marketing field peas.
"You have to be really careful harvesting them so you don't split too many, the other thing is controlling pea weevil and heliothis, to make sure you don't get holes in the peas from the bugs," he said.
"If the quality gets downgraded it knocks your marketing and price around a lot."
He said they harvested their field peas early and kept the rotor speed on the header low to minimise splitting.
"The other thing is not moving them through augers too much, we use belt elevators as much as we can."
