Hydrangeas bloom in so many colours, so there’s guaranteed to be one that suits your garden aesthetic.
Gardeners can choose from whites, greens, purples, pinks, blues and even multicoloured options too.
But when you hear of the magical, colour-changing abilities of these enchanting plants, it relates to a specific variety called hydrangea macrophylla, or “bigleaf hydrangea”.
Bigleaf hydrangeas are known to bloom in shades of pink, blue, or white. While white varieties will remain pure and untouched by colour regardless of what you do, pink and blue hues can be influenced by the soil they grow in.
The secret to changing the colour of hydrangea flowers isn’t what’s applied to the blooms themselves, it actually has to do with the chemistry of the soil.
He said: “It can be added to the soil on potting or planting or, for established plants, dissolve the hydrangea colourant in water and water your hydrangeas with it every week during the growing season (March to September).
“If you do this, then your light pink varieties will turn pink varieties will turn mauve-blue.”
Hydrangea colourant can be picked up from many garden retailers – one of which is the Westland hydrangea colourant at Crocus for £5.99 and another is from Thompson and Morgan for £5.99.
Gardener on the Gardening Hints and Tips Facebook page even raved about these products. Paul Cresswell wrote: “I have used ericaceous compost and hydrangeas colourant and it works a treat.”
Orla Cahill said: “For blue your hydrangeas need to be planted in acidic soil. If you don’t have acidic soil you can use ericaceous compost.”
Alexander Vandervolk commented: “I use hydrangea colourant from Westland, just sprinkle a handful under the base of the hydrangea and water in.”
Remember, flower colour isn’t going to change overnight. There’s a reason that blue hydrangeas are a hot commodity.
It’s a slow process that takes time and patience, but with some diligence, you can create the perfect, acidic conditions that blue-hued hydrangeas love.
Hydrangeas that are blue or purple can also be made pink with kitchen scraps, according to gardening fans.
