Most items in Monster Hunter Rise can be carved from the corpses of creatures, though this isn't the case for all materials. Rock Roses actually have to be gathered from nodes, but where can you find them? Find out below!
How To Find Rock Roses
Rock Roses can be found in the Sandy Plains though they can be quite rare, look out for a Desert Rose node, which looks like a load of rocks stacked on top of each other in a basket, odd description I know. These nodes can be found all throughout the desert and harvesting them will give the player Rock Roses. You'll find these items in the rocky area halfway between 4 and 9. There's also some right near area 2, pretty much on the icon for the '2'.
How To Use Rock Roses
Collecting Rock Roses will reward the player with Kamura Points which can then be used to send out Meowcenaries, otherwise, you can use them to meld items in the Melding Pot. Aside from the aforementioned use, Rock Roses are also a necessity when it comes to upgrading your Argosy, you'll receive a side quest that requires the roses in order to unlock another ship.
There a load more materials and resources to find in Monster Hunter Rise, you can find plenty of guides on how to find them here.