Naku Weed in Genshin Impact is located in the Inazuma region and will only grow there. The plant is said to vibrate to the sound of thunder on windless days and is a deep purple cover with a pointed triangular shaped main leaf that looks like a flower.
Naku Weed can be found growing in several groups around the islands. We'll highlight all three below, with maps to show you exactly where the plans are growing.
It's a good idea to collect them as soon as you find them, so you never have to try to track them down specifically. It is good to approach all of the game's assets in this way as a time-saving measure against future farming efforts.
The good news is that you don't have to do anything specific to grow these plants, you can just interact with them and harvest them, and you don't need a specific elementary reaction to do that.
Location of Narukami Island
Naku weeds on Narukami are found around Mt. Areas of the Shrine of Yougou and Grand Narukami.
Kannazukaka locality
Kannazuka resorts are located across the central bay east of Tatarsuna. It should be noted that the arrows above do not represent just a flower and Naku weeds are extremely dense in this area.
Yashioris
On Yashioris, the central canyon running through the north of the islands will be lined with flowers, while others can be found south of Serpent's Head.