Isolating the subject! That’s key. And you’ve done a good job of it with the focal length you chose, getting some excellent depth of field. I like that there’s both blur in the foreground and background. The subject is tack sharp though, and that’s important for flowers especially. Reminds me of shooting the exact same thing in North Carolina last year. 🙂
It’s neat that the light appears to be streaming in only on the flower too. The whole picture makes me feel peace and solitude of a relaxing walk in the woods back to my camping spot after a full day of fun activities enjoying the warmer days of spring.
If I was taking this picture, I would probably have tried to get lower and closer to fill the frame a bit more and to “attach” the background with the foreground. Right now, it feels like the picture is split into two sections, top and bottom, and there’s nothing really connecting them, which makes the background feel detached. Perhaps moving lower would put the trillium against the distant blurry background more making it stand out more than it currently does against the closer background logs. However, doing this would put the flower on the horizontal center so perhaps I would try a horizontal composition putting the bloom at the intersection of the top right third.
Perhaps you composed the shot like you did so you could add text, like a quote or verse of Scripture, above the flower. That would help to fill things in more for sure.