Potted Hydrangeas are best enjoyed as a temporary indoor plant, unless it can be planted in the garden. If so, enjoy your Hydrangea by placing it in the coolest room of your home, near a window where it can get as much light as possible. It is important not to overwater by allowing it collect water at its base or by watering it too often.It is always best to plant the Hydrangea outdoors whenever possible! It should be planted outdoors in early to mid summer, as it needs time to acclimate to outdoor conditions before winter arrives.