Hydrangea macrophylla 'Bloomstar' – Endless Summer Blooms in Captivating Bicolour
Hydrangea macrophylla 'Bloomstar', sold under the Endless Summer collection, is a truly exceptional reblooming hydrangea that delivers wave after wave of colour from early summer right through to autumn. Unlike traditional macrophylla varieties that flower only once on old wood, 'Bloomstar' blooms reliably on both old and new growth, making it far more resilient to late frosts or accidental hard pruning and ensuring an extended, generous flowering season.
The flowers are a showstopper in their own right — large, lacecap-style blooms featuring a ring of showy outer florets surrounding a central cluster of delicate fertile flowers. The petals display a striking bicolour effect, with each floret edged or washed in contrasting tones that shift depending on soil pH: expect vivid pinks and rosy reds in more alkaline soils, transitioning to rich mauves and true blues in more acidic conditions. This colour-changing character adds an element of discovery to growing 'Bloomstar' year on year.
Forming a compact, well-branched mound of glossy deep green foliage, 'Bloomstar' is an elegant and versatile garden shrub. Its tidy habit makes it equally at home in formal borders, relaxed cottage gardens, or as a standout feature in a large container on a sheltered patio or terrace.
Why Choose Hydrangea macrophylla 'Bloomstar'?
Reblooms All Season – Flowers on both old and new wood for colour from early summer to autumn.
Stunning Lacecap Blooms – Elegant bicolour flowers with intricate detail and real garden presence.
pH-Responsive Colour – Blooms shift from pink to blue depending on your soil, offering a personalised display.
Compact & Tidy Habit – Well-suited to borders, beds, and generous containers.
Cold Hardy – More resilient than many macrophylla varieties thanks to its reblooming genetics.
Planting & Growing Conditions
Position: 'Bloomstar' performs best in a sheltered spot with morning sun and afternoon shade, or in dappled light throughout the day. Avoid harsh, exposed positions or prolonged deep shade, which can reduce flowering. A south- or west-facing sheltered border or patio is ideal in cooler climates.
Soil: Thrives in fertile, moisture-retentive but well-drained soil enriched with plenty of organic matter. Soil pH has a significant influence on flower colour — acidic soils (pH 5.5 and below) encourage blue and mauve tones, while neutral to alkaline soils produce pinks and reds. Incorporate ericaceous compost or aluminium sulphate to encourage bluing, or garden lime to promote pink shades.
Hardiness: Hardy in most UK and temperate European conditions, though young growth emerging in spring can be susceptible to late frosts. Planting in a sheltered position and applying a protective mulch over winter will help safeguard the plant and its overwintering buds.
Care & Maintenance
Watering: Keep the soil consistently moist, particularly during warm or dry spells. Hydrangeas are thirsty plants and will wilt quickly under drought stress — regular deep watering is far more beneficial than frequent light watering. Mulching around the base helps retain moisture and regulate soil temperature.
Feeding: Apply a balanced slow-release fertiliser in early spring as growth resumes. A specialist hydrangea feed or ericaceous fertiliser will support healthy foliage and abundant blooms. Avoid high-nitrogen feeds, which can promote leafy growth at the expense of flowers.
Pruning: Because 'Bloomstar' blooms on both old and new wood, avoid cutting back hard in the way you might with arborescens varieties. Instead, in early spring, remove only dead, damaged, or crossing stems, and lightly tidy the overall shape. Deadhead spent blooms after flowering or leave them for winter interest and some protection to the buds below. If old wood is damaged by frost, cut back to healthy buds once the risk of frost has passed.
Design & Planting Ideas
Plant in a sheltered mixed border alongside roses, salvias, and geraniums for a classic cottage garden feel.
Use as a standout specimen in a large glazed container on a shaded patio or courtyard.
Combine with hostas, ferns, and astilbes in a lightly shaded woodland-style planting for complementary texture and form.
Mass plant for a dramatic seasonal display, particularly effective when multiple plants transition through their colour range together.
Excellent as a cut flower — the lacecap blooms are long-lasting in a vase and can also be dried for indoor arrangements.
Hydrangea macrophylla 'Bloomstar' is a sophisticated and rewarding garden shrub that earns its place year after year through sheer flower power and adaptability. Whether you are drawn to its elegant lacecap blooms, its season-long performance, or its enchanting colour-changing character, 'Bloomstar' is a variety that consistently delights — from
