On the Sun and Moon

[Treikayan]

In the Silmarillion, before the sun (Anar) and moon (Isil) illuminate the Ilumen, how do things on the earth grow? I caught a blurb about the nightflowers being mentioned somewhere. The Two Trees of Aman are in Valinor, but it is said that in Middle-Earth, there remained the stars overhead; only the western horizon was illuminated.

When the Sun and Moon do come, it does mention the speeding of age and of things that grow. Is there a place where Yavanna seeded Middle Earth with plants that grow without light? I'm confused. Don't plants need light for photosynthesis, unless Tolkien disregarded that aspect of trees and plants? :P

Also, Anar appears in the West, not the East at dawn. I did read that correctly...right? What about Isil? It is said that his path was irregular and "staggering" behind Anar or Arien.

On the final note, at the beginning, Iluvatar holds three orchestrations before the Fire Imperishable kindles Arda (each time with Melkor causing discord). Are those three orchrestrations about the three ages of Middle-Earth? Or, are they about the three ages of the elder times? The Spring of Arda, The Bliss of Valinor and the Noontide? Hope someone can answer. The book is very interesting.