An interesting thing is happening to my 5 yr old peace lily. It has been flowering continuously for many months. Recently, the spathes turn green soon after emerging and the central flower in each seems longer than before. I feel it may be setting seed, which hasn't happened before. It has 11 spathes at present, lovely but I would prefer its usual white rather than this vivid green! Hope you can explain what is happening. It has been in my garden room extension for 18 months now, in a fairly shady corner, but with a large velux window above it.
The Peace Lily flowers start out green then turn white, and then as they age turn green again. Eventually the flower turns brown before it collapses.
These changes are all due to chlorophyll.
You can remove the flowers when they turn green, if you prefer your plant to have it's white flower appearance.