Spinach is used in the Chef profession and, much like a lot of the other more rare gathering materials can only be found in patches across the world. However unlike a lot of other rare crafting materials out there used in cooking Spinach sells for a ton of money. Usually a silver to a couple silver each. This is one of the few locations that you can port to for the maximum amount (usually 4s 50c is the most you'll pay for porting to any waypoint) and still make money from gathering here.
This location is to the west of the Provern Shore Waypoint which is found in the northern part of this zone.
It's a long run from the nearest Waypoint and there is a veteran troll nearby the Spinach nodes.