Opposition leaders Andrew Little, James Shaw and Winston Peters say New Zealand's reliance on dairy and manufacturing is short-sighted, and Kiwis should be concerned.
It comes after Landcorp scaled back its dairy expansion, Fonterra announced a further drop in milk payout prices to farmers and the Reserve Bank cut the official cash rate to 2.25 percent, from 2.5.
The Labour, Greens and New Zealand First leaders told The Nation official economic figures of 3 percent growth, 5.3 percent unemployment and low interest rates mask the reality of what is going on.
Labour leader Mr Little claimed part of the reason behind the 3 percent growth figure is record immigration, with new residents bringing money with them from overseas.
Mr Shaw, Green co-leader, said while unemployment appears to be down it is being helped in the short-term by construction in Christchurch.
"Manufacturing is having a really good time at the moment but even that is driven by the construction sector, so even that is a temporary thing tied to the Canterbury rebuild," said Mr Shaw.
"Rebuilding Canterbury after a major disaster is not an economic strategy," added Mr Little.
Mr Peters said compared to countries with similar sized populations such as Norway, New Zealand is falling behind.
"One time we used to be way ahead of them and we have failed to keep ahead with smart policies."
The three leaders were mostly in agreement on the best way to boost New Zealand's flagging dairy sector. They claim the problem is Government subsidies.
"They [the dairy sector] have had a free ride in terms of the emissions trading scheme, in terms of water standards and in terms of tax treatments," said Mr Little.
"Andrew's completely right -- the Government incentives have completely skewed the economy here," added Mr Shaw.
"[There was] a $400 million subsidy to go into massive irrigation projects as well, which has incentivised farmers to take frankly quite risky investments and to be farming in areas where they've got high production costs, and now their production costs are well in excess of what they can get on the international market."
They also agreed the way the agricultural industry is structured means New Zealand exports an excess of basic products such as whole milk powder, instead of adding value through further local development.
Mr Shaw said the Greens have been pushing for dairy to invest more in higher-value organic farming for years.
"It's only now Fonterra is starting to offer farmers an actual market rate for organic, and organic is selling for $14,000 a tonne as compared to about $2,800 a tonne for regular."
National party leaders refused Newshub's request to participate in the debate.
What the leaders would do for the economy: