For summer-flowering shrubs with impressive blooms and lovely foliage, here are five of the best...
Carolina allspice (Calycanthus floridus) is a large summer-flowering shrub (3m high, 2m wide), with dense, glossy leaves and rich red flowers that open from fat buds along the stems. It gives a glorious flush of blooms in early summer, then flowers on and off through to September. A sun lover, its sweet, spicy scent is similar to stewed apples and cinnamon (all parts are scented but only the bark is edible).
Mock orange (Philadelphus) has an intense, citrussy perfume that hangs in the air on warm summer evenings. Elegant yet tough, it shrugs off urban pollution, wind and salt-laden air, and has an abundance of flowers from June to July. Excellent varieties include the compact ‘Manteau d’Hermine’ (1m high), with double white blooms, and the taller ‘Belle Etoile’ (1.5m high), which has single flowers with purple-splashed centres.
Hydrangeas are super popular and rightly so: they’re low-maintenance, unbothered by pests and diseases, and flower for months. Mophead types (macrophylla) change flower colour depending on the soil – pink on alkaline or blue on acid/neutral – and age to soft, smoky tones. Pompom types include the frothy lime-white Hydrangea aborescens ‘Annabelle’. Or you could opt for cone-shaped paniculata, like ‘Vanille Fraise’, whose flowers turn from white to pink, then red. All need space to breathe, spreading 1-3 metres. The mopheads need partial shade to stop flowers fading. Other varieties tolerate sun but all need plenty of watering.
New Zealand tea tree
If you’re looking for a spectacular summer-flowering shrub that’s a magnet for pollinators in your garden, try the New Zealand tea tree (Leptospermum ‘Red Damask’). An evergreen with aromatic leaves, it has bright red buds in spring that open to nectar-rich, double flowers – the source of famous manuka honey. A compact shrub, it’s also a striking choice for a container or sheltered bed sitting in full sun.
For a summer-flowering shrub with architectural lines, the Japanese snowball (Vibernum ‘Kilimanjaro Sunrise’) is hard to beat. Voted Plant of the Decade by the People’s Choice at this year’s virtual RHS Chelsea Flower Show, it looks glamorous in a border, in front of a wall or in a generous container. It has an attractive pyramid shape and tiered branches covered in flat, lace-cap flowers that open white and become suffused with pink. The heart-shaped leaves turn fiery shades of orange and red come autumn. Slow-growing, it will eventually reach 2-3 metres tall, and is happy either in sun or partial shade.