Minister Shane Rattenbury this week confirmed he will stand for re-election but former colleagues Caroline Le Couteur and Meredith Hunter each referred questions to party convenor Sophie Trevitt.

The party would not comment on who has nominated for preselection, instead preparing to announce the successful candidates in October or November.

The process is being run alongside preselection for the next federal election. On Saturday, high profile former Senate candidate Simon Sheikh said he would not stand again in 2016. Labor and Liberal jockeying is also under way.

Ms Trevitt declined to say how many party members had put their names forward or if the former members would stand, but said she expected Greens candidates would be on the ballot in each of five new ACT electorates.

All fully-paid up party members can vote in preselection. Candidates will make speeches and prepare personal statements for consideration in the vote.

"It is unlikely that we will run five candidates in each electorate," Ms Trevitt said.

"I can't comment on who has put their hand up or who will put their hand up before our membership is made aware of that.

"From what I know about the people who have put themselves forward, we have a very strong and diverse array of people ... ages, skills and lived experience."

The former Assembly members were surprise losses for the party in the 2012 election, leaving Mr Rattenbury as the sole balance-of-power Green, forming a governance agreement with Katy Gallagher's Labor Party.

Former Greens member Amanda Bresnan did not return calls for comment on Monday.

Mr Rattenbury, who has grown his profile as a prominent minister for Territory and Municipal Services, said the party was very optimistic going into next year's election campaign.

He and Chief Minister Andrew Barr have pledged cooperation for the rest of the current term.

"The way that the electoral boundaries have been drawn present a great opportunity for the Greens to rebuild our numbers in the Assembly," Mr Rattenbury said.

"I have a view that we were unlucky in 2012. We missed out on two more seats by just a couple of hundred votes in both Ginninderra and Brindabella. We feel we can bounce back at this election and we've certainly got a lot of people in the party nominating as candidates."

"Our membership is at record levels so we're feeling confident that there is momentum for the Greens."

Former candidate Jonathan Davis has nominated for the Tuggeranong electorate, Brindabella.

The 23-year-old real estate agent said he was optimistic about winning preselection but declined to discuss his key campaign issues. Mr Davis said the Greens were winning support from Canberrans because of the party's good record.

"Standing in the 2012 ACT election as a support candidate was an awesome experience and over the past four years I've been connecting with the community and building up my capacity as an MLA," he said.

"I am excited now about the contribution I might be able to make."

Former public servant and staffer Kim Fischer will seek preselection for Labor in the Belconnen seat, Ginninderra. Ms Fischer, who worked as an electorate officer for former Fraser MP Bob McMullan and for Education Minister Joy Burch, has lived in Canberra since 2002.

Factionally unaligned, she said former chief minister Jon Stanhope and Labor prime minister Gough Whitlam were among her political role models.