I think you have two options. You can choose a bright color, such as yellow to contrast your green design, or you can choose a more subtle color to keep with the neutral tone. I’d go with the second idea and choose a lighter beige toned rug. Here’s an example I found on Amazon.
I’d recommend something like this which has a mix of both dark and light colors and would look really good near your bed. Found this on Amazon.
I don’t have a rug suggestion (sorry!), but I think a sofa ottoman chaise would looking amazing in your bedroom. Your bedroom is already beautiful, and the ottoman would add a touch of glamour and take it to the next level! Here's an example of one:
I will suggest you light color near your bed.
A light, neutral colour at the end of your bed would complement the neutral walls really nicely!
I suggest you to use dark colour near your bed. This will be not getting dirty soon.
Try Custom rugs that add beauty to your room