Strawberry Sundae hydrangea

Sun

Full sun to partial shade; give afternoon shade in hot climates. Too much shade reduces flowering.

Water

Keep the root zone evenly moist but not waterlogged. Water deeply during dry spells, especially in the first two growing seasons and when grown in containers.

Soil

Moist, well-drained soil enriched with organic matter; tolerates clay if drainage is adequate. Acidic to slightly alkaline soil is suitable, and soil pH does not control flower colour.

Height

4-5 ft (1.2-1.5 m)

Spread

3-4 ft (0.9-1.2 m)

Flowers

Summer into autumn; creamy-white flower heads age through pink to deeper pink or strawberry red. Colour intensity varies with temperature and growing conditions.

Foliage

Oval, pointed, toothed green leaves; deciduous, with usually modest autumn colour.

Growth

Moderate, sometimes faster with steady moisture and good soil.

Care needed

Low

• Cold hardy
• Wildlife
• Low allergen

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

Difficulty

Easy

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

   2.3 ft (0.71 m)

3. After 2 years

   3 ft (0.93 m)

4. After 3 years

   4 ft (1.1 m)

5. After 5 years

   4 ft (1.4 m)

   full size

About 4 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

Fast

• Water deeply when the upper soil begins to dry; do not let newly planted shrubs repeatedly wilt.
• Apply 2-3 in (5-8 cm) of organic mulch in spring, keeping it clear of the stems.
• If growth is weak, apply a balanced slow-release shrub fertiliser in spring at the label rate; avoid heavy nitrogen feeding.
• Use a large, frost-resistant container with drainage holes if growing in a pot, and check its moisture frequently in warm weather.
• Shelter from drying winds and strong afternoon sun where summers are hot.

Pruning. In late winter or early spring, remove dead, damaged and crossing stems, then shorten the previous season's shoots by about one-third if shaping is needed. It flowers on new growth; avoid severe annual cutting, which can produce oversized flower heads on less supportive stems.

Late winter

Remove old flower heads and prune before new growth starts.

Spring

Plant into workable soil, water thoroughly and mulch the root zone.

Spring

Feed lightly if needed, particularly where soil is poor or the shrub is container-grown.

Summer

Check soil moisture during dry weather and water deeply before prolonged wilting develops.

Autumn

Leave sound flower heads for winter structure, or remove them where heavy snow is likely to weigh down the branches.

Late autumn

Check mulch and protect container roots from severe freezing in cold regions.

• Plant as a low, informal flowering hedge along a path or boundary, allowing room for its mature width.
• Use in a mixed border with cranesbills and ornamental grasses for contrasting leaf shapes and late-season colour.
• Group several shrubs against a dark evergreen backdrop to make the pale summer flowers stand out.
• Grow as a specimen in a large courtyard container where regular watering is practical.

Garden styles it suits: Cottage garden, English country, Traditional, Romantic rose garden, Small-space and Autumn colour.

Plant it with: Hardy geraniums, Daylilies, Switchgrass, Coral bells and Hostas.

Wildlife: The showy flower heads are dominated by sterile florets, so this is not a strong nectar or pollen plant. Its branching provides some shelter for small garden wildlife.

• Wilting or scorched leaf edges: water deeply, maintain mulch and provide afternoon shade in hot sites; check drainage before adding more water.
• Few flowers: move to a brighter position if heavily shaded, avoid excessive nitrogen and do not prune after spring growth is well underway.
• Leaf spots or powdery mildew: improve airflow, water at soil level and clear fallen affected leaves; minor late-season damage rarely needs treatment.
• Drooping or broken flowering stems: avoid hard annual pruning and excessive feeding; remove damaged stems and provide discreet support if needed.

Toxic if eaten by cats, dogs, horses or people. Leaves and flower buds contain cyanogenic compounds, and other parts should also be kept out of reach; ingestion most often causes digestive upset, while serious poisoning is uncommon. Seek medical or veterinary advice after ingestion.

• Vanilla Strawberry hydrangea (Hydrangea paniculata 'Renhy')

  Has a similar white-to-pink flower progression but usually grows substantially taller and wider; young plants can be difficult to distinguish without a reliable label.

• Bobo hydrangea (Hydrangea paniculata 'Ilvobo')

  Usually remains shorter and more compact, with abundant white flower heads that generally age a softer pink rather than a strong strawberry red.

• Bigleaf hydrangea (Hydrangea macrophylla)

  Usually has broader, thicker leaves and rounded mophead or flat lacecap flowers rather than pointed cones; many varieties have pink or blue flowers influenced by soil conditions.

The species name paniculata refers to the branched flower clusters, while Strawberry Sundae describes the creamy-white flowers developing strawberry-pink tones.

Propagation. Softwood cuttings taken in late spring or early summer can retain the cultivar's characteristics, but check local plant breeders' rights or patent restrictions before propagating. Seed-grown plants will not reliably match 'Rensun'.

Accepted botanical name

Hydrangea paniculata

In the US and Canada

Introduced in Canada and the lower 48 states.

Native range

China North-Central, China South-Central, China Southeast, Japan, Kuril Is., Sakhalin and Taiwan.

Measured

Average height 580 cm.

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