In the United States the hydrangea is traditionally grown in the garden as an ornamental. Hydrangea blossoms range from pink to blue to red, all of which are surrounded by deep green foliage. For year-round enjoyment, these natives of Asia can easily be grown indoors allowing you to use the softball sized blooms as part of your décor. As a plant that thrives in cooler conditions, the flowers of the hydrangea can live for more than one month when properly cared for.
Place the hydrangea where it will receive indirect light and where it will not become overheated, as this is a plant that does not do well in warm conditions. For example, place the hydrangea near a window rather than directly in front of one.
To produce it's sizable blooms the hydrangea requires a lot of water, so add a little each day to ensure your plant has adequate moisture. Once a hydrangea has finished blooming, its water requirements will decrease.
Fertilize blooming hydrangeas twice a month with a general purpose, water soluble plant food. Follow the package directions, doubling the recommended amount of water as indoor hydrangeas have less rigid nutritional requirements than those planted outdoors. When the plant is not in bloom, feed it once a month.
Cut the spent blooms from the stalk as soon as the flowers fade. This will help the plant to conserve energy, encourage growth and improve the plant's overall health.
Move the plant outdoors to a shady location once the temperature is regularly higher than 50 degrees F, taking care to bring it back indoors if the temperature rises above 70 degrees. This can help to encourage a second round of blooming in the same calendar year.