Important: Hyacinths for indoors needs a cold period (9 degrees C. or less) and needs to keep in the dark till the whole bud is out of the bulb. (the outshoot becomes thinner under the bud). Then you can put the bulb direct in the light by higher temperatures. You can put prepared hyacinths planted between 15 en 20 September mostly in the beginning of December into the light.
