where can gromsblood be found?  Someone should make a map of where each herb can be found

Gromsblood can be found in Blasted Lands. I found some while riding to the Dark Portal.

Also about the comment about there should be a map for all the herbs...  You can get the addon Gatherer and everytime you gather a herb,mine, treasure it records it on your map. It also records through the guild, for instance if someone mines copper in Elywin Forest, you can go to map and to Elywin Forest and there will be a little copper icon where it was mined. This also works through your party the same way through the guild.

Aurthorne
Ysera Alliance

al lot of gromsblood can be found way way south of forst song in ashenvale. forestsong is it the very north-east corner by the elite dragons

grey area on the map when u desovered it, where a load of deamons are that look more like elementals