Tosca Hydrangea

Tosca Hydrangea (Hydrangea macrophylla 'Tosca') is a bigleaf hydrangea that grows to about 1.5m tall and wide, with large rounded mophead flowers that are most often a warm rose. Depending on your soil the heads can swing towards lilac or sky blue, or stay a softer pink, which makes it a living pH test. It is happy in the ground or in a tub.

Why you'll love it

• A flower that tells you about your soil. Warm rose is the usual result, while softer pinks, lilac and blue shades turn up in other soils, so each garden gets its own surprise.
• Large mophead blooms. Big rounded heads in a spread of colours stand out against soft light green leaves.
• Movable colour. In a tub you can move it to where the flowers harmonise best with their neighbours.
• Solid mid-size shrub. At 1.5m by 1.5m it fills a bed without overwhelming a small garden.
• Classic cottage character. Its relaxed shape suits cottage, woodland-style and cutting gardens.

Where it works best

Containers and tubs. Use a pot at least 50cm wide, so you can shift it around as the colour develops.

Mixed beds. Plant 1.2m apart in rich soil and let the tops of the shrubs meet. It looks best in group planting.

Woodland and cottage gardens. Underplant with ferns, and place it where it gets morning sun and afternoon shade.

Growing Tosca Hydrangea in Australia

Position and climate. Choose a partly shaded position, with protection from harsh afternoon sun. It suits cool temperate and warm temperate gardens. In subtropical gardens, plant it in deep afternoon shade with extra water.

Soil. Rich, moist, well-drained soil. Pinker tones come from alkaline or chalky soil, bluer tones from acid soil, and lilac from neutral pH.

Water and feed. Water regularly for the first 8 to 12 weeks, then give plenty in dry periods. Top up with a slow release fertiliser as the new leaves appear in spring.

Pruning. Next summer's buds sit on last year's stems, so avoid hard cutting. Snip off spent blooms above a pair of healthy leaves. All parts are toxic if eaten, to people and pets.

What to expect when it arrives

We sell Tosca Hydrangea as tube stock only. Tube stock is a young plant in an 80mm deep tube that establishes quickly once planted. Plan for leaf growth first and flowers building over the first couple of seasons. It travels upright and should be potted on, or planted out, soon after it arrives.

Plants are delivered Australia wide, with delivery from $29.95. Every plant is covered by our 30 day healthy plant guarantee.

Plant care guides and related reading

• Shop all hydrangeas
• Changing hydrangea colour with soil pH
• How to lower soil pH for bluer flowers
• Plants for partial shade

Common questions

Can I make Tosca blue?

You can nudge it. Acid soil gives bluer shades, so lowering the pH gradually can help, but expect the change to take a season or two and the result may be a lilac rather than a true blue.

Why is it a surprise colour?

The flower shade follows the soil, so the same plant can open warm rose in one garden and lilac or blue in another. Tosca is usually a warm rose.

Is it hard to grow?

No. Give it morning sun, afternoon shade, rich moist soil and regular water, and avoid cutting it back hard.