Question
I am forcing paperwhite bulbs in shallow bowls filled with gravel.  The leaves are between 18-22" tall so far and are beginning to show the bulges where the flowers will emerge.  I'm concerned because the leaves have developed black streaks and are falling over.  What can I do to resolve this problem?

Answer
I can think of a couple of things that may be happening.  It is possible that the leaves are too long (22" sounds like it) and are weak in structure and may be bending at certain points and then they develop the black streaks where they bend.  This may be caused by low light.  Try moving them to a slightly brighter place. The other possibility is a bacterial disease.  You can try to get some copper fungicide from a garden center and mix according to label instructions and spray the foliage once per week.  Do not spray flowers when they emerge.