My experiments with forcing spring flower bulbs in water began on Dec. 4, 2014 when I filled a round blue bowl-type vase about a third full with clear glass marbles, poured in enough water to cover the marbles, and set about two dozen of the small grape hyacinth (muscari) bulbs on top of them.
They were in my living room, which stays on the cooler side, between 55 to 60 degrees, as a little-used room.
About five of the bulbs didn't sprout as quickly as the others, so I took those out and put four of them in a square vase with green marbles in the window of a sunny bedroom that was about 68 to 70 degrees on average. A few weeks later, I put the bulb shown in the top of a cobalt blue jar and set it in front of a textured privacy window of a bathroom that stays a little cooler because it is on an exterior wall.
The funny thing that happened was that all of the bulbs bloomed around the same time.
The slow-starters didn't grow as tall as those in the living room. They might have benefitted from more light from the south-facing window. But the single bathroom bulb was in shade and cold and it still bloomed along with the others.
What does this say? Every flower blooms in its own time, as the saying goes. All told, it took about 10 weeks for the flower buds to appear in the blue vase planting. I also planted muscari bulbs very close together in the large bowl of a thick-stemmed cocktail glass as a gift for a friend. For whatever reason, that one took longer to bloom in a different environment. It was in flower a couple of weeks later, taking 12 weeks total.
Muscari is recommended for water forcing because the bulbs are so easy to grow. Our flowers didn't develop perfectly, however. There was more space between the florettes than there should have been. So this year, I'll start them in the basement for a six-week cold treatment along with the tulips to see if they perform better with a little chill.
The process is simple: Start with clean vases and fillers. Use a weak bleach solution (2 teaspoons of bleach in a gallon of water) to clean vases and soak all stones, marbles or other fillers for 10 minutes. Rinse well and dry.
Next, fill each vase with an inch or two inches of marbles. With muscari, the roots wrap around the marbles, so smaller marbles seemed to be better. Because grape hyacinths are small plants, the marbles can be filled almost to the rim of a decorative planter with bulbs set on top.
Add water just to the top of the marbles and set the bulbs on top, with pointed end up. To avoid rot, don't let the bulb bottoms sit in the water. Even if the water level is a little low, the roots will grow down to get a drink. They actually seem to thrive when you don't lavish them with attention and constant water refills. Of course, give them more to drink before the vase goes dry.