There are a total of 6 Udumbara Flowers in the new desert area and you need them to complete the Pale Fire Quest (which will be covered in the next guide). Here are the locations for all 6 of them and how to harvest them.
Udumbara Flower locations
➥ To collect the Udumbara Pistils, use Sorush and HOLD (not press) E when you are near the heart-shaped rock. Once Sorush are floating in front of the flower, you climb the cliff or anything to reach the top of the now blooming flower. The image above mark the location of all 6 Udumbara Flowers.
1. Teleport to Asipattravana Swamp west waypoint and keep walking east from where you spawn (just walk straight). Jump off the cliff and glide until you see 3 Fungi staring at the heart-shaped rock on your right.
2. From the previous location, face northeast and walk towards it. Use the Four-Leaf Sigils to glide across the canyon and you will see the next heart-shaped rock. There is a Special Four-Leaf Sigil that Sorush can move so you can move the Sigil to on top of the flower.
3. Teleport to Asipattravana Swamp north waypoint and turn around facing the Vourukasha Oasis (the large tree with green energy coming out of it). Glide off the cliff and look back towards the cliff. There is a Special Four-Leaf Sigil below the Udumbara Flower (on top of a cactus) so you can move it.
4. From the previous location, look back towards the Vourukasha Oasis and glide down to the large rock in the middle of the canyon with the Soul Bell on it. There will be an Udumbara Flower on the rock.
5. From the previous location, turn around and you will the next Udumbara Flower. There are 2 normal Four-Leaf Sigils you can use to reach the Udumbara Flower.
6. Teleport to the Vourukasha Oasis north waypoint just before a bridge. Glide northwest until you see 1 dancing Hilichurl facing the heart-shaped rock.