Ravensdown - the fertiliser farmer co-operative - has capped the price of its superphosphate product to give farmers a firm number to budget with.
Chief executive Greg Campbell said the product's price will be fixed at $320 a tonne until the end of November.
Superphosphate is a fertiliser used on dairy, livestock and cropping farms.
Mr Campbell said the company's balance sheet was in good health, which allowed it to delay any possible price rises.
He said this was a first for the company.
"We've probably not done something like this before, where we've capped it for a period, which means what we're saying is that the price won't go up any further. If we have an opportunity to take it down during that period, and it may occur, but ... our shareholders can plan with the certainty that it won't be going up any greater than what it is today, until November 30th.
He said the price of $320 tonne was quite stable.
"It's a pretty good price. A number of shareholders have said we can see what's happening with the exchange rate, knowing that potentially it might have to lead to a price increase at some time, so being able to hold the price for that period will be met with some benefit to them."
Mr Campbell said farmers would be able to budget and buy with slightly more certainty before applying it in spring.