Twist-n-Shout hydrangea

Sun

Morning sun and afternoon shade; tolerates more sun in cool climates if the soil stays moist. Avoid hot afternoon sun in warmer regions.

Water

Keep the root zone evenly moist but not waterlogged. Water deeply during dry spells; containers need more frequent checks.

Soil

Humus-rich, moisture-retentive, well-drained soil. Acidic soil with available aluminium encourages blue flowers; less acidic soil usually produces pink flowers. Avoid strongly alkaline soil.

Height

3-5 ft (0.9-1.5 m)

Spread

3-5 ft (0.9-1.5 m)

Flowers

Early summer into autumn, depending on climate; pink, purple or blue lacecap flower heads, influenced by soil chemistry.

Foliage

Broad, toothed, dark green leaves, sometimes developing burgundy tones in autumn; young stems are reddish.

Growth

Moderate

Care needed

Medium

• Pollinators
• Heat tolerant
• Low allergen

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Moderate

Toughness

Fairly tough

Pick your zone, country, light and whether you have pets.

1. Planting day

   1.6 ft (0.5 m)

2. After 1 year

   2.1 ft (0.64 m)

3. After 2 years

   2.6 ft (0.78 m)

4. After 3 years

   3 ft (0.92 m)

5. After 5 years

   4 ft (1.2 m)

   full size

About 5 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Toxic

Growth rate

Moderate

• Water at soil level when the upper soil starts to dry; do not rely on brief showers to soak the root zone.
• Apply 2-3 in (5-8 cm) of composted bark or leaf mould in spring, keeping it clear of the stems.
• Feed lightly in spring with a balanced slow-release fertiliser; avoid heavy nitrogen feeding, which favours leaves over flowers.
• Protect emerging shoots from late frost with horticultural fleece when practical.
• Use a generous container with drainage holes if growing in a pot, and check its moisture frequently in summer.

Pruning. In spring, once buds begin to swell, remove dead wood and cut old flower heads back to the first strong pair of buds. Avoid cutting the whole shrub down in autumn or early spring, as this removes the old stems that carry the earliest flowers.

Late winter

Leave old flower heads in place in cold districts and check that mulch still covers the root zone without touching the stems.

Spring

As buds swell, remove dead wood and trim off old flower heads above strong buds.

Spring

Apply mulch and a light feed; plant new shrubs once the soil is workable.

Late spring

Protect tender shoots if frost is forecast.

Summer

Water deeply during dry weather and check containers frequently.

Autumn

Avoid hard pruning and stop feeding; water during prolonged dry spells before winter.

• Plant along an east-facing wall or foundation for summer flowers without intense afternoon heat.
• Group beneath open-canopied trees with ferns and hostas, allowing enough space to limit root competition.
• Use in a mixed shrub border with camellias and azaleas where soil conditions suit all three.
• Grow in a large patio container where its lacecap flowers can be seen at close range.

Garden styles it suits: Cottage garden, Woodland, Traditional, Romantic rose garden, Blues and silvers and Small-space.

Plant it with: Hostas, Japanese painted ferns, Astilbes, Camellias, Azaleas and Japanese forest grass.

Wildlife: The small fertile flowers provide pollen and nectar for visiting insects. It is not a native food plant in the United States, Canada, the United Kingdom or Australia.

• Few flowers: winter damage, late frost, hard pruning or excess nitrogen may be responsible. Preserve live old stems, protect emerging buds and feed lightly.
• Wilting or scorched leaf edges: check soil moisture and water deeply if dry; provide afternoon shade in hot sites. Do not add water to already saturated soil.
• Leaf spots or powdery mildew: improve airflow, water at soil level and clear fallen diseased leaves.
• Yellow leaves with green veins: alkaline soil can restrict iron uptake. Test the soil and use an appropriate chelated iron treatment; grow in a container if the garden soil is strongly alkaline.

Toxic if eaten by cats, dogs, horses or people. All parts contain cyanogenic compounds, with leaves and flower buds a particular concern. Ingestion usually causes digestive upset, but larger amounts can cause more serious poisoning; seek medical or veterinary advice after significant ingestion.

• Mophead hydrangea (Hydrangea macrophylla, mophead cultivars)

  Mopheads have rounded heads dominated by large showy florets; Twist-n-Shout has flatter heads with a visible centre of small fertile flowers.

• Mountain hydrangea (Hydrangea serrata)

  Usually has smaller, narrower leaves and a finer-textured habit. Lacecap forms can look very similar, so a reliable label is needed for confident cultivar identification.

• Climbing hydrangea (Hydrangea anomala subsp. petiolaris)

  Has white lacecap flowers but grows as a woody climber with clinging aerial roots, rather than a rounded, self-supporting shrub.

Hydrangea comes from Greek words meaning water vessel, referring to the seed capsules, while macrophylla means large-leaved.

Propagation. Softwood cuttings in late spring or early summer, or layering a low stem, preserve the cultivar's characteristics. Seedlings will not come true; check local plant breeders' rights and propagation restrictions before taking cuttings.

Accepted botanical name

Hydrangea macrophylla

Native range

Japan and Kazan-retto.

Measured

Soil pH 4.5 to 8. Average height 150 cm.

Sources: GBIF (CC BY 4.0) and Trefle (CC BY 4.0). The care and design notes are LandscapeGPT's own.