Once you've completed the main story quest The Living Seed in New World, you'll have to help Adiana Theron find the source of an Azoth fountain blockage in the Canary Mine.
The quest chain will eventually lead you to confront the Corrupted at Ebonrock Cavern, but first you'll need to craft a Corruption Tincture as part of the quest Weakness of the Ego.
One of the ingredients you need for that is Petalcap. Here's where you'll find it.
Where to find Petalcap in New World
Petalcap is a resource yielded from the Fronded Petalcap plant, which resembles a kind of lotus.
A useful plant, it can also yield the following:
- Green Pigment
- Mushroom
- Mushroom Fins
- Toadstool Fringe
- Fungal Slime
- Fungal Spores
- Glowing Mushroom Cap
Fronded Petalcap image credit: Kornstaticxguy via New World Wiki
There are two areas of the map where you'll find Fronded Petalcap nodes in abundance.
The first is in the south of Aeternum, in the Territory of Windsward, while the second is in the east, on the Restless Shore.
You can see the nodes marked on the maps below, from the New World Interactive Map.
Luckily, the Fronded Petalcap can be gathered by anyone, as it has a Harvesting level of zero.
Nodes will respawn every 15-30 minutes.
Farming these nodes is ideal in the creation of various tinctures and potions, thanks to the T2 and T3 reagents you'll harvest.
Examples include the T3 Strong Health Potion and T3 Strong Endurance Potion that use the Petalcap itself, and various Ward and Absorption potions and tinctures that use Fungal Spores, Toadstool Fringes, and other reagents gathered from the Fronded Petalcap.