Possible Clues:

• Images backing US city article -- second is making things greener
• Pictures, strangely shiny, set in process that gives everything more life
• Chemical process stops this honey becoming runny
• The posy this son arranged, showing what plants can do
• This posy's on the ground — it requires chlorophyll
• Flowers keeping warm, last of light shines out — it makes the garden grow
• Process by which plants trap light energy
• Rejected New York paper with pictures identifying plant process