Note: This mission can be completed only after finishing Retaking Thirsk !
Obtaining Juniper Berries for Elmus of Thirsk Hall can cause you some trouble – the plant doesn’t grow anywhere on Solstheim. In order to obtain it, you will have to return to Skyrim and look for it nearby Riften or in the basin between Kartwasten and Sundered Towers (western part of the map).
Some alchemists can also sell this rare ingredient. If you bring even one piece to Elmus, you will complete the mission and receive an amount of gold depending on your level.