Species

Hydrangea macrophyllaBigleaf Hydrangea

52 other cultivars

shrub

Endless Summer Hydrangea

Hydrangea macrophylla 'Bailmer'

The Story

Plant Bio

Hydrangea macrophylla is a deciduous, rounded shrub native to East Asia, characterized by its large, opposite, serrated leaves and prominent flower clusters. The species thrives in moist, organic, well-draining soils in partial shade, with flower coloration shifting dynamically based on soil pH and aluminum availability.

'Bailmer' is a remontant cultivar that produces large, globe-shaped mophead blooms on both old and new wood from summer through fall. This continuous blooming habit ensures reliable flowering even if late spring frosts damage the overwintered buds.

Uses & Benefits:

Produces massive, color-shifting mophead flower clusters from summer through fall against deep green foliage.

Offers a highly forgiving blooming habit that tolerates late spring frosts and mistimed pruning better than older cultivars.

Provides occasional nectar for generalist pollinators and nesting sites for native bees in hollow dead stems.

SpeciesHydrangea macrophyllaBigleaf Hydrangea

Essentials

At a Glance

Plant Type

Shrub

Height

48"

Width

48"

Light

Partial Sun, Shade

Zones

4, 5, 6, 7, 8, 9

Water

Medium to high

Humidity

Moderate to high

Lifespan

Multi-year

Native To

Asia

Toxicity

Low severity toxicity

Bloom period

Summer – Fall

In flower about 6 months of the year

Planting

How to Grow

Plant in a location with partial or dappled shade, avoiding intense afternoon sun unless the soil remains consistently moist.
Amend the planting site with rich organic matter to ensure a moisture-retentive yet well-draining soil structure.
Apply a three-inch layer of organic mulch around the root zone to conserve moisture and regulate soil temperature.
Water deeply and regularly, especially during hot, dry summer spells, to prevent the large foliage from wilting.

Pro Tip

Because this cultivar initiates buds on current-season growth as well as previous-season wood, it is highly forgiving of spring freezes and mistimed pruning that would otherwise prevent flowering on traditional cultivars.

Keep It Thriving

Care Guide

Do

Apply aluminum sulfate to the soil in early spring if you want to encourage intense blue flowers.
Apply lime to the soil well in advance of blooming if you prefer pink or lilac-pink flowers.
Prune dead or weak stems in late winter or early spring to maintain a clean structure.

Don't

Do not allow the soil to dry out completely, as the large leaves wilt rapidly under moisture stress.
Do not plant in poorly drained areas where standing water can cause root rot.
Do not perform heavy annual pruning, as it is unnecessary and removes potential early-season blooms.

Seasonal Care Calendar

Task	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Fertilize
Mulch
Pest Check
Prune

Watch Out For

Pests & Diseases

Common Pests

Common Diseases

In the Garden

Landscape Uses & Companions

Landscape Uses

Foundation plantingMixed shrub bordersCottage gardensContainer specimen

Companion Plants

Hosta Astilbe HeucheraFerns

Multiply

Propagation Methods

Good to Know

Common Questions

Endless Summer Hydrangea questions

What zones can Endless Summer Hydrangea grow in?

Endless Summer Hydrangea is hardy in USDA Zones 4–9. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.

Is Endless Summer Hydrangea deer resistant?

Not reliably. Deer may browse Endless Summer Hydrangea, especially tender spring growth — plan on repellents or fencing where pressure is high.

When does Endless Summer Hydrangea bloom?

Endless Summer Hydrangea typically blooms in summer through fall. Exact timing shifts a week or two with your zone — Sow's bloom calendar maps it to your garden.

Does Endless Summer Hydrangea need full sun?

Endless Summer Hydrangea does best in part shade.