No credit to me, just a link to another great guide by Catnip over on the Steam Community forums.https://steamcommunity.com/sharedfiles/filedetails/?id=18496...
Following this guide will net you the "Rose Petal", "Rose Bud", and "Bouquet" achievements.
Like many other Artifex Mundi games this one does have multiple points-of-no-return. So you will want to make sure you grab the collectible on each screen as you get there. Most screens (but not all) will have a single rose design that fades in and out, never more than that.
One note: There will be screens where a scene or conversation occurs before you can interact with the background/pick up the rose. This is always safe so don't worry.