Why did JOhn get off at Coketown?

Nothing more than a ragged hillside, Coketown, is where John deboards. The author was surprised if Pescud was to sell plate glass there. Then John told the author that the other day he took Jessie on a little trip to Philadelphia and how while coming back she thought she saw some petunias in a pot in one of the windows on the way. She used to raise some at her Virginia home. So he thought to drop off at Coketown to dig up some of the blossoms for her.