He said that despite the best efforts of the election engineers the Green Party occupies a “distinctive and unique place on the political landscape.”

Speaking on the new political context with a minority SNP administration he added: "Some opportunities come from the mere fact of minority government. In the new Parliament – and in every one of its committees – the parties meet without a pre-engineered majority to force everything through. That'll pose problems sometimes, but I believe it will more often lead to real debate, and force Ministers to keep an open mind to new ideas.

"Opportunities also come from our own culture and attitude. There are some politicians who are so tribal, so blinkered that they can't see past the party whip. There are others across the spectrum who can acknowledge deeply held differences, mark them, and move on to explore common ground with a constructive attitude.

“I have always been proud to see how Greens I've met anywhere in the world share the latter attitude. Our ability to co-operate with others despite our differences is one of the most important reasons I feel at home in this party, and it will stand us in good stead for working within the dynamic environment which minority government brings."

Discussing the forthcoming crunch vote on the Scottish budget he said that the “tight” parliamentary arithmetic means that his and fellow Scottish Green MSP Robin Harper’s votes will be crucial.

"The SNP may want to tell themselves that good results on the football field and the buoyancy of a successful Commonwealth Games bid is all they need to sustain a political honeymoon which need never end. But soon, they may find that Mr Salmond's one liners aren't enough.

He said that in order to gain the Greens’ support the SNP will have to show that some of the most “damaging” aspects of their spending plans have been “tempered”. In particular he asked whether the Greens could “in good conscience” support a budget that fails to cut subsidies to aviation, proposes road building schemes, and lacks funding for the social rented housing Scotland needs to eradicate homelessness and investment to cut energy consumption in Scotland's homes and businesses.

However, he did offer his support for the SNP’s ‘National Conversation’, saying: "Other opportunities arise from the SNP's 'National Conversation'. Instead of the constitutional chaos which their opponents predicted, they want to present an open discussion about the country's future, and the other parties are finding that they can do nothing but edge gently toward some middle option- more devolution, but short of independence.

"But when such middle options are talked about, they're always designed to further the goal of a high-consumption Scotland. Our part in that national conversation needs to place the priority on the goal of a sustainable Scotland – presenting the only rational long term vision for the country's future."

Delegates also heard from former MSP and outgoing Scottish Green Party co-convener Shiona Baird, who closed the conference. Baird said it had been a “roller-coaster of a year” for the party. However, she added: “Despite a massive effort by the Party and all the candidates, the vagaries of the electoral system and pressure of party politicking rather than policy issues, squeezed us in Holyrood but enabled us to burst out into local government.

“It proves you just can't keep a good Party out.”

She said that Glasgow and Edinburgh have “thrown down the gauntlet to us all” and that they must take it up with “renewed vigour” to ensure that the party has councillors in every council in Scotland who can make sure that “real action” is being taken on climate change and social justice.

She continued: "After 24 years I remain convinced that we have the right economic, social and environmental policies to lead this country to a sustainable future. We have made a considerable difference already and we must continue to make a difference in the future.”

She also praised her successor, Councillor Alison Johnstone, leader of the Green group on the City of Edinburgh Council will take over from Baird as the new co-convener of the Scottish Green Party, adding that she knows she is leaving the Party in “very capable hands”.