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Hydrangea colourant

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Quick and easy treatment to change pink hydrangeas to blue. Made from iron and aluminium salts, the powder acidifies soil to make hydrangea flowers bloom in stunning blue. Darker pink varieties will turn a deep mauve-blue.

Best results are obtained with plants already growing in acid soils. Where soil is naturally alkaline, use ericaceous compost instead or double the application rate.

How to use:

When planting, apply 50g (one capful) per square metre and mix into soil. Every 7 days during growing season, dissolve 50g in 5 litres of water and apply to the soil around the shrub, avoiding foliage.

Please note: white flowers will not change colour, and some pink hydrangeas are bred to keep their colour in all soil conditions so will remain unchanged. Make sure to check the plant label before use.

Key features:

  • Turns pink hydrangeas blue
  • Enhances colour of all lime-hating shrubs
  • Simple application

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PR30008268
500g
£5.99
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Delivery options (pick your preferred option at checkout)
Standard delivery Standard Delivery£5.95
Nominated delivery Named Day Delivery£10.95

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