They may make you think of your gran but she was onto a good thing with hydrangeas. Not only can they be grown just about anywhere in Australia they also flower prolifically in blue, pink, red or white.
Hydrangea macrophyllais the most widely recognised species. The mophead type has big round flower clusters while lacecaps feature long, flathead open blooms with bud-like flowers in the centre.
Older varieties tend to be larger, while the newer are smaller, with an extended flowering time and brighter colours. There are also miniature types that get to about 300mm high.
Anthony Curnow of Plants Management Australia says that hydrangeas are simple to plant but need nutrients to thrive.
Says Anthony, ‘Make sure you dig plenty of organic matter into the soil. Be aware that, depending on what you add and the soil type, the colour of the hydrangea may change over time.’
It’s true that Hydrangea macrophyllaflowers can change colour, depending on the acidity of the soil.
More acid soils give blue flowers, alkaline soils red or pink and neutral purple, while white stays white regardless of soil pH.
Anthony says it’s best to accept the colour you have but to change the blooms, add lime to the soil for pink flowers or aluminium sulphate for blue.
You need to change the soil pH before the flower buds form so it’s best to treat the soil after August.