You can make the stems less floppy by adding alcohol to the water!
> Start your bulbs in plain water. Most folks use containers filled with stones or marbles. Press bulbs, nose up, stones, with the tops sticking out. Leave half of the bulb above the stones.
> Fill container so that the bottoms of the bulbs are just touching the water.
> Keep at room temperature in a well-lighted area. After shoots emerge, keep out of the direct sun (otherwise the foliage will stretch toward the sun). When roots have formed and green stem shoots are 1 to 2 inches long, pour off the water and replace with a solution of 4 to 6 percent alcohol. If you are using 80 proof liquor (40 percent alcohol), that works out to one part gin (or similar) to 7 parts water.
> Rubbing alcohol (70 percent isopropyl alcohol) can be substituted; just remember to dilute it more. Mix 13 parts water to 1 part rubbing alcohol.
> Don't try beer and wine. They contain sugars that damage plants.