Bigleaf hydrangea (Hydrangea macrophylla 'Bailmer' ENDLESS SUMMER)
Reliable reblooming Bigleaf hydrangea, Hydrangea macrophylla 'Bailmer' ENDLESS SUMMER, thrives in Zones 4-9. Features pink-edged white flowers in part shade.
Scroll down to discover growing tips, care requirements, companion plants, and more
Complete Plant Information
Overview
The Hydrangea macrophylla ‘Bailmer’ ENDLESS SUMMER is a highly valued deciduous shrub, renowned for its superior reblooming capabilities compared to many traditional Bigleaf hydrangeas. This cultivar reliably produces flowers on both old and new wood, significantly increasing its season of interest from July through September. Its distinctive bloom color often presents as a lovely pink edged with white, offering consistent color even after colder winters.
As a desirable Bigleaf hydrangea, this selection merges classic rounded shrub aesthetics with enhanced resilience, making it a staple in contemporary landscaping. It features large, dark green leaves that provide excellent texture throughout the growing season, contrasting beautifully with its summer blooms. Its moderate size and low maintenance requirements make it exceptionally practical for home gardeners.
This dependable variety ensures vibrant garden interest across a wide hardiness range, minimizing the gardener’s frustration with lost flower buds during unpredictable winter weather. For gardeners seeking continuous summer blooms from an adaptable shrub, Hydrangea macrophylla ‘Bailmer’ ENDLESS SUMMER delivers reliable performance.
Fast Facts
- Plant Family: Hydrangeaceae
- Plant Type: Deciduous shrub
- Hardiness Zones: USDA Zones 4-9
- Size at Maturity:
- Height: 3-4 ft
- Spread: 3-4 ft
- Bloom Time: July to September
- Bloom Description: Pink edged with white
- Sun Exposure: Part shade
- Water Needs: Medium
- Maintenance Level: Low
How to Grow
The optimal environment for the Bigleaf hydrangea is rich, well-drained soil receiving medium moisture in a location providing afternoon shade. While Hydrangea macrophylla ‘Bailmer’ ENDLESS SUMMER tolerates full sun, this requires consistent, moist soil conditions to prevent scorching during peak heat. For best results, soil treatments to adjust pH should be applied in the late autumn or early spring, well before the growing season begins.
Watering should be consistent, maintaining medium soil moisture levels, as these plants—true to their genus name meaning “water vessel”—dislike drying out. Maintenance is generally low; however, mulch is highly recommended. Apply a 3-inch layer of shredded bark, compost, or peat around the base annually to preserve soil temperature and retain moisture.
Pruning needs are minimal for this reblooming type. If pruning is necessary, restrict it to immediately after the primary flowering period concludes, cutting faded stems back only to a pair of healthy buds. Any weak or winter-damaged wood should be selectively removed in late winter or early spring. Growers in Zone 5 should choose sheltered sites, as even this hardy cultivar benefits from protection against the absolute harshest winter fluctuations.
Landscape Uses
The compact yet robust structure of Hydrangea macrophylla ‘Bailmer’ ENDLESS SUMMER makes it extremely versatile in the landscape. It excels when grouped or massed within a traditional shrub border, creating sweeping waves of color throughout mid-summer. Its manageable 3-to-4-foot stature also renders it an excellent choice for foundation plantings near homes or patios, where structure and reliable periodic flowering are desired accents.
This Bigleaf hydrangea functions perfectly as informal hedging where a formal clipped hedge is not required. For container gardening, ensure pots are large enough to accommodate its mature spread and that drainage is excellent, managing water needs diligently as containers dry out faster than in-ground plantings. Consider pairing it with shade-tolerant perennials like Hosta or Astilbe whose foliage textures contrast nicely with the hydrangea’s large leaves.
Standout Features
Flower Qualities
- Showy
Noteworthy Characteristics
Hydrangea macrophylla, commonly called big leaf hydrangea, is a deciduous shrub with a rounded habit that, in the St. Louis area, typically grows 3-6’ tall and as wide unless damaged by harsh winters or pruned smaller. It generally features serrate, obovate to elliptic, dark green leaves (4-8” long) and large clusters of long-blooming summer flowers in either lacecap form or mophead form. ‘Bailmer’ ENDLESS SUMMER is a mophead-like cultivar that is significantly different from other mop heads currently in commerce today because of its unique ability to bloom on both old and new growth and its extremely good winter hardiness. ENDLESS SUMMER plants produce flower buds not only in fall but also on new growth in spring and summer.
Tolerances
Potential Problems
While generally robust, Hydrangea macrophylla ‘Bailmer’ ENDLESS SUMMER can occasionally suffer from specific issues common to Mophead hydrangeas. Gardeners should scout for susceptibility to leaf spot and mildew, making sure to establish good air circulation during planting to mitigate fungal development, especially in humid conditions. Occasional aphid infestations may occur; these are typically manageable with targeted insecticidal soap treatments if they become bothersome.
Bacterial wilt presents a more serious potential problem, though prevention lies primarily in maintaining proper soil drainage. Never allow Bigleaf hydrangeas to sit in chronically soggy conditions, as this stresses the plant and increases vulnerability to root and pathogen issues. Prompt removal of any diseased or heavily infested foliage prevents the spread of fungal spores or blight to healthy portions of the shrub.
Frequently Asked Questions
What hardiness zones is Bigleaf hydrangea suitable for?
Hydrangea macrophylla ‘Bailmer’ ENDLESS SUMMER is reliably hardy across USDA Zones 4 through 9, offering wide adaptability.
How large does Bigleaf hydrangea grow?
This deciduous shrub typically reaches a mature height and spread between 3 and 4 feet.
When does Bigleaf hydrangea bloom?
The reblooming nature of this plant ensures flowers are present from July consistently through September, often featuring blooms described as pink edged with white.
What sun exposure does Bigleaf hydrangea need?
The ideal requirement is Part shade; however, it can handle more sun if soil moisture is maintained consistently.
Conclusion
The Hydrangea macrophylla ‘Bailmer’ ENDLESS SUMMER stands out due to its dual flowering habit and enhanced winter survival, making it one of the most rewarding Bigleaf hydrangeas available. This low-maintenance shrub provides extended floral display and rich foliage color across diverse regions. Before planting, confirm that your local USDA Zone falls between 4 and 9, and prepare well-drained soil to enjoy its reliable summer performance.
Companion Planting for Hydrangeas
Selecting companions that share the preference for part shade and medium moisture levels will create a harmonious planting scheme around your Bigleaf hydrangea. Consider layering shorter, shade-loving groundcovers beneath them to keep the soil cool near the roots. Hostas provide excellent contrasting foliage texture, especially varieties with chartreuse or variegated leaves that pop against the dark green of the Hydrangea macrophylla ‘Bailmer’ ENDLESS SUMMER.
For vertical contrast, consider ferns such as Japanese Painted Fern (Athyrium niponicum) or woodland phlox (Phlox stolonifera). These plants thrive in similar filtered light conditions. Avoid planting sun-loving perennials directly adjacent, as competition for water could stress the hydrangea, particularly during dry spells when consistent moisture is crucial for reblooming.
Seasonal Care Calendar
Spring preparation is vital for ensuring robust summer flowering. As new growth emerges, ensure your mulch layer is refreshed (3 inches deep) to moderate soil temperature and retain humidity. Late spring is the appropriate time to prune out any remaining dead or damaged wood from the previous winter.
Summer is the critical time to monitor water needs. Because the ENDLESS SUMMER variety blooms on new wood, ample water is essential from June through August when flower buds are actively forming for the second flush of blooms. Water deeply and consistently, especially if exposed to afternoon sun.
Minimal fall cleanup is required; avoid heavy pruning entering the colder months. Allow foliage to age naturally. In colder zones (Zone 4 and 5 edges), a light fresh layer of mulch applied after the ground freezes can offer extra insulation protection for the stems as the plant enters dormancy.
