Bulbs are typically sold in mid to late Autumn. If you'd like your plant to bloom around Christmas time, plant the bulb about 6-12 weeks before you want it to bloom. The timing varies depending on your growing conditions (light, temperature, etc.), so make a note of when you planted it and how long it takes to bloom so you can plan accordingly for the following year. If you want to speed up the rate at which your plant blooms, supplying bottom heat will cause it to grow more quickly. You can either place it on a propagation mat (I've purchased mine on Amazon), or simply on top of a radiator (as long as your plant is still in a sunny location).