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How to Grow Hydrangeas


July 27, 2022


Searles Gardening Team

One of the most colourful flowering plants for the home garden are hydrangeas and summer is the time they show their big bold blooms.

Planting Hydrangeas in gardens

Hydrangeas are easy to grow. Hydrangeas grow best planted in a position where it gets morning sun and is protected from the hot afternoon heat. For planting hydrangeas in garden beds, plant in Azalea, Camellia & Gardenia Specialty Mix for acid-loving blue hydrangeas. For other coloured hydrangeas, Searles Planting Mix is ideal. These mixes will provide all its nutrition needs for the growing season.

Planting Hydrangeas in pots

Some compact varieties of hydrangeas look spectacular in pots placed around patios and high visible areas, eg. pathways and front entrances. Plant up in Platinum Potting Mix. Platinum has plenty of fertiliser and water crystals to keep your flower heads looking big, bright and happy.

Hydrangea in pots - Best potting mix for hydrangea planting


Hydrangea pot plant - Best plants for pot plants

Changing the colour of Hydrangeas – Pink or Blue

Traditionally you could change the colour of your hydrangeas by changing the pH of the soil, though many modern varieties available now are more fixed in their colour. Some white hydrangeas don’t change colour at all. The newer varieties feature bigger blooms and more compact habit. It is worth taking a look at what is available in garden centres.

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 acidic soil. That is soil with a low pH of approximately 5 - 5.5. To make the soil acidic, apply Sulphur Powder to the soil as per label directions.

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.

Watering Hydrangeas

Hydrangeas require regular watering, especially when they are planted in pots. They may also need extra watering during long periods of hot dry weather and summer sun. Keeping the soil moist will help retain those big blooms.

Pruning Hydrangeas

Start pruning after the flowering season, which is usually late Autumn or Winter. Remove rogue branches and older ones that had flowers on it the previous season. This way when your hydrangeas do flower later in the year, the shrub will be more compact and boast newer growth.

Fertilising Hydrangeas

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.

Let us not forget they make long-lasting cut flowers. Buy a hydrangea today and follow your tips for big, bright blooms of colour this summer...