Yes. The leaves of the Philodendron Florida Ghost can develop to a darker green, yet they can revert to white again! Just make sure to provide it with plenty of bright, indirect light. This means that you should carefully move your plant to a spot wherein it should not be directly hit by sunlight since it could damage the leaves, causing it to be dehydrated.  As long as it gets adequate light, its leaves will turn white after several weeks. However, they can become darker if not provided adequate light. A helpful tip that you can do is to position your plant near the window for best results.