Looking at the Green parties principles none seem left wing.
• All political, social and economic decisions should be taken at the lowest effective level.
Down right libertarian in fact probably slightly right wing as almost all these decisions can be taken at the individual level and so will lead to market effects.
• Society should be guided by self-reliance and co-operation at all levels.
• The need for world peace overrides national and commercial interests.
Ever since the invention of nuclear weapons, and the development of the ability to kill everyone, everyone has recognized this to be true.
• The poverty of two-thirds of the world's family demands a redistribution of the world's resources.
This last one sounds left wing but it does not say how redistribution will occur. If it is we will take money from rich people it is left wing. If it is we will free up trade to allow poor people earn more it is right wing.
We Are For...
• A basic income for all citizens.
We Are Against...
• The depopulation of the countryside and over-crowding in the cities.
Like Pol Pot? Left wing
• Control of industry by large national and multinational companies.
Most right wing people would support removal of subsidies on big business so this is not necessarily left wing
• Land and property speculation.
This is left wing.