Bought a couple of bulbs from HD. One already "planted" in water and stones the other in a box. There were no directions so I'm sure I put too much water in the container (or poured water down the bulb.) Anyway, the smell of rotten matter told me I had a major problem. The bulb was growing and already had flower buds almost ready to break out. Anyway, I took the bulb out and cleaned all the dead matter off; washed all the stones and container real well; then proceeded to "replant." There was a small plastic piece that the bulb sits on and then rocks around it. I think I will put the boxed one in potting soil, but have already taken the containered one to my Mom in assisted living.
Think it will make it? I love the looks of them. Can you tell this is my first experience with them? :>)
Amaryllis in water
I have done in on pebbles in water, and it works, but I prefer potting soil, just like any other houseplant. They need some air at their roots. And you can move it over from water to soil at any time. Just don't throw it out after the bloom, plant out side for summer and bring in for another inside bloom. I oversimplify, but that is the idea.
I haven't planted these just in water before, but from the reading I've done, I've learned that you only want the roots of the bulb in the water. You want to be sure that the bottom of the bulb where the roots come from (the basal plate) is not in the water. And, yes, do try not to get water into the neck of the bulb.
Like AnalogDog, my prefered growing medium is potting soil. Be sure to get one that drains well. Plant with 1/3 to 1/2 of the bulb above the soil. Before planting, I usually put some organic time-release bulb food in the soil under the bulb (with some soil between the soil mixed with bulb food and the bulb).
Others prefer to feed their amaryllises with a diluted liquid fertilizer when they water them. And, you'll want to let the soil dry out a bit between waterings.
Hope this helps!
Michelle