New Home is next to Capital and neither are filled with flowers and trees. What your describing could either be Snowdin or Waterfall. Still, this is worth investigating. It's also possible New Home could be one of the reflections.

I doubt past me over here would agree to be dragged through the dirt, so you might have to carry him.

[Flowey lifts Asriel into the air and over to Anya.]

Just make sure he doesn't try going through. I've already had to deal with a crazed, paranoid Azula.