Former Green MP Nandor Tanczos has warned his party against a deal with the National Party this year - but says it has to be an option in the future.
Tanczos, an MP from 1999 to 2008 who is now a Whakatane district councillor, said during a campaign to co-lead the Greens in 2006 that the party should be prepared to go into coalition with National some time.
But he says in a new blog post that doing a deal with National now would be "both impossible in practical terms and politically suicidal".
"Impossible because any coalition agreement needs ratification by 75 per cent of the party and there is more chance of Winston retiring gracefully from politics," he writes.
"Suicidal for a multitude of reasons. First, people voted for the Greens on the clear understanding that we would not support a National Government. To do so would be a complete betrayal of our voters, akin to NZ First going with National in 1996 (for which they got badly punished).
"Second, it might be worth the risk if we could shape the trajectory of an incoming government. To bolster a government almost certainly in its last term, a government that has shown such disregard for both the environment and our growing social inequality, just before their support collapses, would be a tragic mistake.
"Third, to make such a move without lengthy preparation and discussion inside the party would tear the Greens apart."
But he said the Greens "must be prepared to seriously consider the idea" of a coalition with National at some stage.
"If Greens cannot carve out a constituency beyond the 'left of Labour' cul de sac we are in, we will continue to play out the dynamic of this election over and over, soaring in the polls only as long as Labour is doing badly, but dropping back to 5 per cent as soon as Labour turns left again. Or finds a charismatic leader," Tanczos writes.
"We may be mighty in opposition, but we will always be puny in coalition until we stop relying on discontented Labour voters for support."
He said a left/right continuum "is simply incapable of representing Green politics".
"Our most defining issues don't figure on it at all and neither are the solutions to them a simple application of any one ideology, whether ecosocialism or green capitalism," he said.
"Both the left and the right have valuable contributions to make to this discussion, but more important for the Greens is the opportunity to articulate uniquely Green solutions as the third point in a left/right/green triangle.
"In fact, if you look at the fundamentals, there is very little genuine political difference between National and Labour....
"Because if you look at the most fundamental Green concerns - climate change, protection of waterways, child poverty, growing inequality, protecting civil and human rights, tangata whenua rights - the last Labour government was barely more progressive than National."
Tanczos urges the Greens to connect with New Zealand's 450,000 small businesses.
"Self-employment speaks to core Green ideals of supporting local economies, building self-reliance and personal autonomy, helping people lift themselves out of poverty and fostering stronger linkages between businesses and the social ecological communities in which they are located," he said.
"I know a great many small business owners who support the ideals of the Greens but who don't connect with us a party because we are not speaking to them.
"There are actually lots of Greens who are small business owners - probably a disproportionate number compared to either National or Labour.
"Both National and Labour tend to focus on large corporate bureaucracies and pay little attention to how their policies impact on small businesses - who as we know are New Zealand's biggest employer.
"For years the Greens put loads of effort into trying to woo the unions. It would be worth putting the same effort into understanding how to support a sustainable, resilient and regenerative business ecology. Certainly no one else is doing much in that space.
"Escaping our 'left of Labour' trap is not about 'moving to the centre'. The very notion of a centre sitting half-way between Labour and National is irrelevant when we locate ourself on a triangle.
"Neither is it about 'abandoning our principles'. Rather it is about embodying them in their entirety. What they cannot mean, though, is relegating ourselves to the periphery of power just because we are committed to giving Labour a free run."