Start at Brena River north of Anvil, you will see an inlet that curves in just before it turns in to a river to head east. Start searching for Nirnroot there and work your way south on the outter shoreline. You should pick up 15 Nirnroot Plants here alone. The last one being on the island a little ways up The Serid River.
East of Kvatch the road will go north and then turn to the east, head north off the path and you will find a lake with a Nirnroot at its edge.
North east of Kvatch you will find a settlement called Shardrock, next to this settlement is a pond with two Nirnroot.
West of Chorrol head along The Black Road and you will come to a lake about three-fourths of the way up the road with a Nirnroot by it. Near the dock just off the path.
On the northern road of Skingrad that wraps around the cities northern side. You will see a pond on the west side of the path, search in the tall plants for the Nirnroot.
North east of Skingrad at Shadeleaf Copse you will find three Nirnroot located around the lake, Sinderion will mark it on your map when you talk to him.
Head south of Leyawiin on the west coast and go all the way south on the shore to reach the section that won’t let you go any more south. Turn back around and head up along the coast to grab all the Nirnroot along the way. Remember to head in to the river inlets all the way around the edge. Go north up and around the Imperial City and then make your way back down to the east coast side near Leyawiin. You should get around 40 by the time you reach the long bridge crossing the south east river towards The Yellow Road on the west bank alone.
Continuing from the above spot on the west bank, continue to wrap around the outter still wrap around the outter edge of the lake and then go around the shore of the island holding the Imperial City itself. You should find around 35 Nirnroot along the way.
From the large bridge that crosses towards The Yellow Road head along the shore to the south and go up all the rivers along the way to collect more Nirnroot. You should be able to find at least 45 Nirnroot.
Head down the road south of the Imperial City called The Green Road leading to Bravil through the Great Forest. Once you reach Charcoal Cave at the top of the waterfall, cross the bridge and turn left looking at the rocks for a plant called a Sprig of Nirnroot.
Head in to Bravil and cross the eastern bridge towards the castle and go along the castle wall to the south west corner to find another Nirnroot.
In Bravil head to the south wall and go behind the house for sale. Along this back wall in the south east corner just before the cliff is a Nirnroot plant.
In the Smuggler’s Cave in Anvil. Enter the wooden door from the cove and turn to the north and search near the waters edge.
On the way to get the Arrow of Extrication you will come across a small shallow water area after the deep pool, on the edge of this shallow water area is a Nirnroot to grab.
In the captains quarters on the pirate ship in the Waterfront at the Imperial City is a Nirnroot on the captains dining room table.
At the end of the dock to the east by the pirate ship near the water is a Nirnroot just sitting there.
Go to Leafrot Cave just north of Panther River’s middle branch, which is north east of Leyawiin. Check along the north north west side of the pond right next to the left side of the large boulders for a Nirnroot.
Outside Leyawiin along the north wall, west side of the river running past, a Nirnroot will be next to some rocks.
On the east side of the river on the south side of the Old Bridge south of the Imperial City is a Nirnroot.
On the bottom floor of the tower of Fort Redman without entering the actual fort look behind the ruins stone stairs to find a Nirnroot growing back here.
In Anvil on the east side of the mermaid statue near the water is a Nirnoroot.
Inside your bedroom at Frostcrag Spire add-on is a garden it is next to the rock on the right.
At the dock north west of Weye just outside the Imperial City at Lake Rumare.
In Chorrol enter the house of Vilena Donton and head up to the third floor, next to the bed is a flower pot with a Nirnroot inside.
North west of Amellions Tomb by the large tree is a Nirnroot.
In Leyawiin, on the second floor walkway of the Blackwood Company Hall there is a pot on a small table with a Nirnroot in it.
In Leyawiin, in Jeetum Ze’s Room in the Blackwood Company Hall, you will find a Nirnroot on the dresser near the south wall.
In Cheydinhal, during your recommendation you have to go in to the well under the water. Go the opposite way from where Vidkun’s body is and you will find a Nirnroot on the ground in at the dead end. Nothing is in the water to attack you.