This year’s local elections have now kicked off in earnest. There’s no polling in London this year, so I’m not standing anywhere but, as Principal Speaker, I went up to visit local parties in Norwich and Colchester last weekend to help with canvassing and launching their local campaigns.

Norwich hardly needs the help. They already have nine city councillors and two county councillors and look set to break through in new areas this year to become the second largest party in the city. After the launch photos in the town centre I helped canvass in a ward where they currently don’t have a councillor and had trouble finding anyone who wasn’t Green-friendly. Similarly in Colchester, the doors in the ward where we aim to get our first borough councillor elected were a joy to knock on.

At the local shopping centre in Norwich I also helped the local ‘bag ladies [2]’ (really a campaign to replace plastic bags run by the ‘Women Acting to Keep the Planet Unpolluted and Peaceful’ group) to promote their new design competition to create a reusable green shopping bag for Norfolk to rival the madly trendy, sold-out several times ‘I am not a plastic bag’ by designer Anya Hindmarch.

Gorgeously, both Colchester and Norwich had devised itineraries that involved putting me on a rickety bike to get from place to place – does that happen in any other party, I wonder? I couldn’t complain, except about the heat after I’d failed to read the weather reports and worn my big winter coat while everyone else was in vests. (Note to self: climate change means you can’t rely on April weather in April any more.)

Last Monday I joined Caroline Lucas MEP, London AM Darren Johnson, Councillor Keith Taylor from Brighton and my fellow Principal Speaker Derek Wall, for the main national launch of our local election campaign. We picked a room in Millbank Tower, of all places, to hold the press conference. Caroline said that, just as New Labour had vacated the building, now it was time for them to vacate local government. Seeing as Labour are only standing in two thirds of council seats this year, it’s something they seem to be taking on board already.

The most exciting fact about these local elections is the virtual guarantee that we’re going to exceed an average of 10% of the vote where we stand, after getting a tantalising 9.75% outside London in 2006. We’re fielding a record number of candidates so we’re standing for the first time in some places, but we should break through the threshold without a problem.

An average of 10% sounds impressive enough, but its full significance doesn’t become clear until you look back through our historical results in local elections. People outside the Green Party are always pointing out to me the received wisdom that ‘the Greens aren’t as strong now as they were in 1989’. The 15% we got in the European elections that year is still seen as the ‘high point’ of green politics in the UK, and as something we’re still trying to repeat.

But, in fact, a glance at the local election results from 1989 (an average of 8.6%) shows that this year we are going to do much better than we did then, and now with more than twice as many candidates and many more chances of winning seats.

The thought that we have quietly created a new ‘high point’ – and that this is the result of a record of success and a solid build-up of support, rather than a sudden rush of interest – has helped keep me in a good mood all week.