Hydrangea macrophylla.

• Deciduous shrub with large, spectacular flower heads in different shades of blue, pink and many more.
• Normal size about 1-1.2 m high, there are dwarf varieties as well.
• Perfect for pots and in ground.
• Ideal position with morning sun and shade in the afternoon. Their big green leaves get burnt easily by the sun. 
• Keep roots cool by a good thick mulch.
• Acidic soil for blue flowers, alcaline for pink. You can buy already made solutions.
• Very hardy and reliable. Low maintenance. Does not have to have moist soil (except in the beginning), will take dry spots.
• Main flowering spring and summer. Remember to water extra when in flower.
• Flowers are good for cutting, fresh or in dried flower arrangement.
• Cut back in winter when their leaves fall off, this will thicken them up for spring.