The proposed 'blue-green' party has launched a crowdfunding website in the hopes of gauging public interest and attracting financial members ahead of the election year.

Vernon Tava's Sustainable New Zealand party is pitched as an environmental party that - unlike the Greens - is willing to work with National.

The party need at least 500 members in order to be on the ballot in the election.

Leader Vernon Tava told Mike Hosking that's what the website is hoping to achieve.

"It will take some doing...but I am confident that it won't be too much trouble finding at least 500 New Zealanders who are interested in a party that will put the environment first, that doesn't bring a whole lot of other ideology in with that, and is able to work with any party that is in government."

When asked what a quintessential blue-green policy is, Tava took issue with the blue-green label.

"I don't mean to be pedantic but I have to say, the blue-green name, I think, infers the party is a right-wing party with an environmental gloss, and I think that we have seen the limitations in that."

"So I would say this is a green-green party, it's one that puts sustainability at the centre of things, and sustainability, of course, is environmental, economic, social and so on..."

He said the most important policy for the party will focus on New Zealand's freshwater.

"Our rivers and our lakes in New Zealand. We know they are under a lot of strain from all sorts of things, like dairy infrastructure, but also the pollution that comes from towns and cities and it's not a single one point problem. That's an absolute top priority."

When challenged over how that differed from the Green Party's freshwater policies, Tava said, that's one of the problems.

"That's one issue and we need an integrated plan for dealing with this, which we don't have."

"Which is evidence based...isn't just about saying, 'well we have to kill dairy', which is still by far the biggest part of our economy."

"It needs a balance...we can't just stack up more rules [or] stricter rules which are difficult for people to comply with, we also have to look at enforcement."

He said the party isn't just an environmental party, it's also very focused on the economy.

"We have an economy that relies very, very heavily on exploiting natural resources and the environment and these aren't highly productive industries either.

"Our reliance on dairy and tourism means that we provide mostly low-income jobs and the best way for us to improve our eniroment...is to transition our economy to a more sustainable one."

Tava said the aim now is to get the party up and running as soon as possible.

Former National Party president Michelle Boag told Kate Hawkesby there are plenty of National voters who are also environmentally driven.

She said the party will appeal to people who dislike the Green Party's social policies.

"It certainly is designed to be a centrist environmental party because the Greens have said they will never deal with anyone other than Labour."

"So for those who genuinely want a centrist green movement, then, I think, those are the people they are aiming for."

Boag said it is inevitable that the party will take votes away from National but she says there will also be widespread interest from other voters.

"There are a lot of National Party voters, myself included, who do want to see the environment at the centre of our policies, and sustainability."

"There will also be supporters who just want to see sustainability at the centre of policies but don't want to be tied into a leftist agenda."

She said she has full confidence in Vernon Tava's ability to lead the party.

"He's a very smart person, he's articulate, the website works well, I think he has done a good job all by himself."

"I think he is a credible force in New Zealand politics."

Boag said the crowdfunding is a way of testing the waters to see how much support the party will get.