Scene 2 act 2 takes place in the Capulet orchard late at night. In what 2 ways does darkness influence what happens in the scene?

The first way that darkness influences in the scene is
that Romeo could not even be there if it were not dark.  Since the two families hate
each other, for Romeo to be seen in Capulet's garden would surely cause him to be put to
death, as it would be assumed that he was there to cause some sort of trouble.  Juliet
says, "If they do see thee, they will murder thee" in line
70.

The second way that darkness influences in the scene is
that it prevent Juliet from knowing that Romeo is there when she starts speaking. 
Because she is unaware of his presence, she openly states her feelings toward Romeo,
something she would never do if she knew he could hear her.  She later tells him (lines
85-87), "Thou knowest the mask of night is on my face;/ Else would a maiden blush
bepaint my cheek/For that which thou has heard me speak tonight."  Since she has
expressed her love, their relationship progresses much more quickly than would be normal
(she doesn't have to play "hard to get"), leading to their extraordinarly hasty
marriage.