Gardeners urged to use one thing to ensure their blue hydrangeas stay blue

Gardeners eager to preserve the striking blue colour of their hydrangeas can now rely on a simple tip from horticultural experts. Many gardeners have been dismayed to find their once vivid blue hydrangeas turning pink, a transformation attributed to soil PH levels by fervent gardening enthusiasts.

There are measures you can take to prevent this colour shift, including a slight adjustment in your watering method. While some may routinely use a garden hose or a watering can, it's the variety of water and your geographical location that can significantly influence the growth outcome of hydrangeas.

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Indeed, for blue hydrangeas, the care they receive can lead to a bounty of different shades. If you're in an area with hard water, the tap water's alkaline nature could be why your blue blooms are changing to pink. Conversely, rainwater, with its inherently more acidic quality, encourages the blossoming of blue flowers in hydrangeas.

The German quality assurance body for plant substrates, Gütegemeinschaft Substrate für Pflanzen e. V (GGS), advises gardeners to use rainwater.

For "special care" to maintain that evocative blue colour, GGS suggests positioning hydrangeas in a "shaded or partially shaded spot to maintain the blue flower colour" since intense sun exposure can also influence the flower colour.

"Water regularly and use exclusively rainwater with a low calcium content," GGS advises, pointing out that "water with a high level of calcium content will increase the soil pH level in the medium term", potentially altering the colour of your cherished blooms.

"As a result, aluminium ions will no longer be available to the plants and consequently not reach the flowers."

The guidance also suggests exclusively using special hydrangea fertiliser, which aids in "maintain the soil's acidity and also contain aluminium sulphate".

According to the Royal Horticultural Society (RHS), as detailed on their website, you can gather rainwater "from the roofs of homes, garages, greenhouses and other garden structures as long as they have gutters and a down pipe that enters the drain at ground level".

This water can then be stored in a water butt for use on your plants, reports the Express.

On another note, if you're seeking an additional straightforward method to enhance the vibrancy of your hydrangeas, Susan Conforte McNeill, a seasoned gardener and the brains behind Susan Said What, has divulged a clever trick involving an item you might never have considered.