Hydrangea Macrophylla is a deciduous shrub producing large heads of tiny flowers in various shades. 

It is perfectly for indoor growing. In this case provide a bright light, in a cool room and plenty of water. You will, then, be rewarded with a long flowering season.

If you buy a hydrangea labelled as indoor, you can plant it in the garden once the weather is mild (May). Indeed, these have been 'forced' and they will need a time to get used to the outdoors.