Every year about this time I start my forced paperwhites. This year's batch have been hanging out in the dark cool garage for a few weeks, and now that they've got small stems and some roots, they're ready to come in the house.
This year I'm trying something new. Replacing the water at this stage with a mixture of water and alcohol is said to stunt the growth of the stems while allowing the flowers to grow to full size. The point is to prevent the stems from flopping over just as the flowers start to bloom.
You can use either rubbing alcohol (I couldn't find any) or distilled spirits (I found plenty). With booze, mix one part alcohol to seven parts water. The best way to do this is to pour out the water in which the bulbs have been rooting (it will probably be sort of brown and smelly anyway) and replacing it with a solution you have measured carefully. As with people, too much alcohol is not a good thing.