A rainbow of Hydrangea Colours

Few garden plants create such instant joy as hydrangeas. They are lush, generous, and filled with colour that lasts right through summer. From soft greens and creamy whites to deep pinks, mauves, and blues, every hydrangea tells its own story.

Whether you grow them in the ground or in pots on a shaded patio, they’re remarkably easy to care for. Here's a few fascinating tips that make all the difference.

1 | Not All Hydrangeas Are the Same

Some hydrangeas have a delightful secret; their flowers can change colour depending on the soil. Others, however, stay true to their natural shades no matter what you do.

• Can shift shades: Hydrangea macrophylla and H. serrata
• Keep their colour: H. paniculata, H. arborescens, H. quercifolia, and most white or green varieties

Fun fact: In certain soils, a pink hydrangea can soften to lilac or even blue tones as pH levels change — nature’s own chemistry show!

2 | The Secret Behind Their Colour

Many hydrangeas — especially the Hydrangea macrophylla types — have a charming trick: their flower colour can gently shift depending on the soil they grow in.

It’s not just “pink or blue.” Soil acidity moves the blooms across an entire colour spectrum:

• Acidic soil (pH 5–5.5): brings out cool tones — clear blues, lilacs, and blue-purples.
• Neutral soil (around pH 6): creates soft lavenders and mauves.
• Slightly alkaline soil (pH 6.5–7): reveals warmer pinks, magentas, and even red tones.

Tip: Deep reds and purples won’t suddenly turn blue. They usually soften toward violet or mauve as the soil becomes more acidic. Pale pinks may cool into lilac, while blues can warm toward purple in neutral soil.

If you’re curious about your garden’s soil, Cape Garden stocks easy-to-use pH meters to help you measure acidity levels. Once you know your pH, you can fine-tune your soil and feeding to achieve your preferred colour balance.

For gentle guidance in either direction:
• Grow Green Organics Acid Mix — keeps soil naturally acidic.
• Wonder Shake ’N Grow Blue Hydrangea Food — deepens blue and purple tones.
• Wonder Shake ’N Grow Pink Hydrangea Food — brightens pink and red hues.

3 | Hydrangeas Love Comfort

They’re happiest with morning sun and afternoon shade providing just enough light for strong blooms without the harsh midday heat. Add bark & mulch around the base to keep roots cool and moist, and water deeply twice a week during hot weather.

4 | Pots & Small Spaces

Hydrangeas are perfect for containers too. Use a quality potting mix, ensure good drainage, and feed regularly. Pots let you move plants to just the right light and keep them looking lush all season long.

Adding hydrangeas to your garden is guaranteed to make you smile. Their blooms bring instant joy , whether brightening your beds outside or filling a vase inside your home. Shop your favourite hydrangeas in every colour at Cape Garden or on our online shop.