The “Alberta Greens” Green Party of Alberta has been de-registered by Elections Alberta as a political entity in the Province of Alberta. De-registration of the party is an administrative opportunity to re-organize and rebuild the party into a viable political organization. The importance and mainstream acceptance of the Green Party’s values and principles are on the rise, and the Green Party's many supporters can now look forward to a fresh start.
As I understand it, when Election's Canada de-registers a riding association its due to financial issues, as this message from party HQ suggests.
More links from Daveberta. The issue was indeed financial.