Punnets were selling for as low 80 cents in Coles supermarkets on Sunday, which is excellent news for fruit lovers, but not so great for farmers.

While some farmers blame a strawberry glut in Queensland and Western Australia, others say the big supermarkets are forcing prices down to unsustainable levels.

"Coles and Woolies and IGA control the market," strawberry grower Lillian McMartin said, from Queensland's Sunshine Coast.

"[They] have ridiculous prices which are below our cost of production."

Ms McMartin, who has been running McMartin's Farms for 30 years, said it cost her about $1.40 to produce a punnet.

"If Coles and Woolies are selling them for 90 cents, you can see farmers will lose money," she said.

"The last three years it's been bad. It's getting worse."

Ms McMartin said supermarkets bought direct from large scale distributors, who sold at lower prices, rather than off the market floor.

"The prices were so low we had to stop picking early," she said.

Ms McMartin also blamed an overproduction of strawberries Australia wide and overseas sellers "flooding" the market for the current glut.

President of peak industry body Strawberries Australia, Sam Violi, said the cheap prices this year were "unusual".

"I've seen it down to $1 or 99 cents," he said.

Mr Violi said the low prices were a result of a longer than usual Queensland season coupled with the start of the WA season.

"We are having a clash of two states and a bit of an oversupply at the moment," he said.

Mr Violi suspected some Queensland strawberry growers would stop producing early due to the low prices.

However, he said he didn't believe that big supermarkets were undercutting small scale farmers.

Mr Violi said the Victorian season was due to start in October, with farmers hoping the price would rise beforehand.

"As growers pull out there will be less supply in the market and the price will start to improve," he said.

"From what I've seen around, [the strawberries] are looking very promising."

Coles Fresh Produce general manager Brad Gorman said the low price of strawberries coincided with peak seasonal conditions for the fruit in Queensland.

"We have a large number of direct relationships with strawberry growers across Australia and it is important to us that we pay prices that ensure their businesses can continue to grow and be sustainable," he said.

"As the availability of strawberries fluctuates throughout the season so do prices to ensure supply and demand are matched in the market."

A Woolworths spokesman said the supermarket's "great relationships" with their strawberry suppliers, along with peak growing conditions in Queensland, meant they were able sell the fruit at low prices.

Blueberries are also being sold at bargain prices - down to $3 a punnet from $7.

Australian Blueberry Growers Association Victorian representative Joel Deveson said there had been a growth in production of the fruit in Queensland and New South Wales.

"The heavy competition with each other, that's what lowers the price because there's so much in the market," he said.

Mr Deveson, who runs Moondarra Blueberries in Gippsland, also said a rise of good quality blueberry varieties meant prices for less tasty ones were coming down.

Mr Gorman said blueberries were in greater supply due to a significant increase in plantings, improved growing techniques and greater varietal development.​

IGA was approached for comment.