THIS state election was meant to represent a historic political breakthrough for the NSW Greens - instead they have lost credibility, ground and influence, becoming even more ineffectual.

Federal Greens leader Bob Brown yesterday conceded the party had failed to win the seat of Marrickville, their chance at victory ruined by candidate and Mayor Fiona Byrne 's controversial support for a boycott on Israel.

In the seat of Balmain, where the Greens were expected to romp it in and win their first seat in the NSW Lower House, their candidate Jamie Parker is trailing 86 votes behind Labor's Verity Firth.

However Mr Brown insisted the results were better than expected, with the Greens increasing their vote and gaining an extra MP in the Upper House - even if they no longer held the balance of power.

"This is a record vote in both houses of Parliament for the Greens," he said.

"When it comes to the Lower House it does look very, very difficult to win Marrickville now.

"I would give it to Jamie Parker to win that seat [Balmain] and that will be a real innovation for The Greens."

While Labor and independents were "decimated" the Greens increased their vote by 2 per cent, now totalling 11 per cent.

They now have five MPs in the Upper House with stonemason Jeremy Buckingham, from Orange, elected.

Mr Brown admitted the NSW Greens would need to assess what went wrong with their campaign, particularly in the seat of Marrickville.

He said there was no doubt the controversy surrounding Ms Byrne's comments and support for Israeli goods to be boycotted ruined their chances in the seat.

"I think it [the call for a boycott] had an effect on it and that's my feedback from the electorate.

"It [a boycott on Israel] is not national Greens policy. It will be up to NSW Greens to have a look at Marrickville."

The result in Balmain won't be known for days but the Greens were still hopeful Mr Parker would win.

In the lead up to the election Mr Parker, who is also the Mayor of Leichhardt, accused Labor of a dirty tricks campaign after it was revealed he was involved in companies promoting products Horny Goat Weed and Fat Blaster.

Mr Parker did not appear at a media conference yesterday. Instead upper house MP David Shoebridge defended the Greens' performance, putting a brave shine on what was really a lacklustre political performance.

"There is still a very strong prospect of the Greens having that historic breakthrough in the Lower House," he said.

"The NSW Greens have grown our vote in the Lower House and Upper House.

"That is an historic outcome for the Greens."

Source: TheTelegraph.com.au

Originally published as Greens fail to reach greener pasture