Buttons and the build queue

From Gardens wiki

A building button shows its name and, once you own some, (on / owned). The small parts on its right:

• + / −: switch one copy on or off. Only copies that are on make things, and they're shown with a green bar.
• on / off: switch every copy at once (on buildings that can be switched).
• sell: sell one copy for half of what the last one cost.
• queue: add it to the build queue.

A red bar means you can't afford the next one yet, or the building is short of power.

Build queue

The Queue tab, next to Log on the right, lists what's waiting. The first item is bought as soon as you can afford it, then the next, in order. Remove an item from the list at any time.