One of the most colourful flowering plants for the home garden are hydrangeas, but did you know you can easily change their flower colour to either pink or blue?

Soil pH
Hydrangea flowers can vary from brilliant pink right through to vibrant blue. The hydrangea flower colour is simply determined by the pH of the soil. That is, the acidity or alkalinity of the soil.

It would be wise to buy a pH test kit to test the pH of your soil. This way, you can monitor the pH as it changes, and you can also easily see how far it needs to change. Soil pH test kits are available from leading gardening outlets.

Blue Hydrangeas
For brilliant blue flowers, hydrangeas need an acidic soil. That is a soil with a low pH of approximately 5 - 5.5. To make the soil acidic, apply Searles® Hydrangea Blue to the soil every 3-4 weeks. Start now for wonderful flowering later in the year.

Pink Hydrangeas
On the other side of the coin, to develop their lovely deep pink flowers, hydrangeas need an alkaline soil, that is a soil with a pH of 7-8. To achieve this, apply some dolomite or lime to the soil every 3-4 months.

It is important to start this after pruning, which is usually late Autumn or Winter. This way when your hydrangeas do flower later in the year, the soil pH has already changed so that you end up with either brilliant blue or deep pink flowers. The choice of colour is yours and its easy to do.

In Spring, start to fertilise your Hydrangeas with regular applications of Searles Flourish® Soluble Plant Food. This will promote strong growth and help develop more flower buds, which in turn means a far greater and more colourful display.
So remember

• For blue hydrangea flowers, apply Searles Hydrangea Blue every 3-4 weeks
• For pink hydrangeas, apply lime or dolomite every 3-4 months.
• In spring, start fertilising with Searles Flourish® Soluble Plant Food. Searles Flourish® is easy to apply by either a watering can, bucket or a hose-end adaptor.
Choosing the colour of your hydrangeas is great fun and if you follow these easy steps, they'll look fantastic.


Happy Gardening with Searles from the Searle family.

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