When I first got my 2013 Nissan LEAF, it was late January and the day I took delivery the temperature high was around 32 degrees Fahrenheit. That night on my way home I had to stop at a quick charge (CHAdeMO) station. I didn't know how to get the climate control to turn on while charging and as the temperature dropped into the teens, I only charged long enough to make it home.
Shortly thereafter, I figured out that one of the easiest ways to get heat is to use the CarWings mobile app to turn the climate control on remotely. That said, I also recently discovered that it is also possible to do this without the mobile app. So, if you press the start button, without your foot on the brake, the car goes into a mode that allows you to use the radio but will not allow you to control the climate or windows. But, if you press the start button a second time, you have full control over the climate control.
A couple of days ago, I encountered two LEAF ownwers using a CHAdeMO unit and they either didn't know how to engage their heat, or decided that ~30-degrees after dark wasn't that bad. While I used the other CHAdeMO unit, I thought it might be a good idea to share this tidbit.