10 award-winning (AGM) shrubs for containers

It’s important to choose shrubs for containers carefully. Not all shrubs are suited to life in a container, even a large one. These winners of the RHS Award of Garden Merit (AGM) are all good choices, and they have a long season of interest, which is important as containers tend to be sited in prominent positions. Heights are not given as plants will vary with the size of the container and how well they’re fed.

Decorative appeal

‘Hidcote’, a classic garden staple, adds vibrant purple blooms and calming fragrance

Lavandula angustifolia ‘Hidcote’ is a compact, evergreen shrub renowned for its narrow, silvery-grey leaves and aromatic, deep violet-purple flower spikes. It flourishes in south, west, or east-facing positions and performs best in sheltered, drought-resistant conditions. The plant produces small, tubular flowers arranged in dense spikes during summer, adding vibrant colour and fragrance to the garden. Ideal for a low-maintenance landscape, ‘Hidcote’ is appreciated for its hardy nature and decorative appeal. Hardiness rating H5.

An aromatic evergreen

Luma apiculata has small, broadly ovate and aromatic leaves

Although developing into a large evergreen shrub or small tree when planted out in the south west, Luma apiculata enjoys container life. The neat, dark green, pointed leaves are the perfect backdrop for the masses of late season white flowers, which develop red fruits that mature to black and have an appealing sweet flavour. The cinnamon-coloured

Bark is the outermost layer of woody plants (trees, shrubs and woody climbers). It is several cells thick and provides protection against physical damage, disease and environmental stresses. Bark comes in a wide variety of colours and patterns, and these can help gardeners when identifying plants. The fissures and crevices of bark on older plants also creates valuable habitat for many garden creatures as well as lichens and small plants.

Spectacular all year-round

Full, rounded trusses of deep red flowers, fading slightly at the edges, bloom in late spring

Many rhododendrons are too large and too boring when not in flower to be grown in containers, but Rhododendron ‘Dopey’ is different. Its heads of vivid red flowers almost hide the leaves but, after dead heading, its attractive mounded shape and glossy leaves are appealing all summer. Ericaceous

Can refer to either home-made garden compost or seed/potting compost: • Garden compost is a soil improver made from decomposed plant waste, usually in a compost bin or heap. It is added to soil to improve its fertility, structure and water-holding capacity. Seed or potting composts are used for growing seedlings or plants in containers - a wide range of commercially produced peat-free composts are available, made from a mix of various ingredients, such as loam, composted bark, coir and sand, although you can mix your own.

Summer is purple

Prostanthera rotundifolia is a bushy evergreen shrub to 2m, with small, ovate, strongly mint-scented leaves

Prostanthera rotundifolia is less hardy than most of my choices but its container can be moved to a sheltered place or a conservatory for the winter. Dense growth and very small leaves set off the purple summer flowers, shaped rather like those of a small penstemon; they open in such numbers as to smother the plant. The pink form, ‘Rosea’, also has an AGM. Best in sun. Hardiness rating H3.

Silver Queen

Small, fragrant dark purple flowers in summer are followed by dark grey fruits containing sticky pulp

Pittosporum tenuifolium ‘Silver Queen’ is another example of a large evergreen shrub that enjoys container life surprisingly well. The small, slightly wavy-edged leaves have creamy edges and an overall silvery caste and the plant’s year-round attraction is augmented by small clusters of honey-scented, chocolate-coloured spring flowers. If necessary, plants can be kept to a given size by thoughtful removal of branches for indoor arrangements. Sun or some shade. Hardiness rating H4.

Prelude of beauty

Not easy to grow in many gardens, they can thrive when planted in containers

Like kalmias and rhododendrons, Pieris japonica ‘Prelude’ need lime-free soil so many gardens cannot grow them but, when planted in containers, they thrive in ericaceous compost. ‘Prelude’ is naturally more compact than most. Its pendulous sprays of pure white flowers, which develop very few inelegant brown pods, are shown off well by the dark foliage and its new foliage emerges bright pink. Best in partial shade. Hardiness rating H5.

Mesmerising pink eyes

‘Little Linda’ is a dwarf cultivar, dense in habit, with untypically small, evergreen leave

Kalmias are lime-hating evergreens with a dramatic burst of June flowers. The compact Kalmia latifolia ‘Little Linda’ has generous clusters of bright red flower

A bud is a small, undeveloped shoot that contains the potential for new growth. Buds are typically found on stems, where they can be apical (found at the tip) or axillary (found between leaf axils) and may develop into leaves, shoots or flowers.

A rock choice

Short spikes of white flowers appear in early summer. A good choice for a rock garden

A neat and very hardy hebe. The small dark evergreen leaves are broadly edged in creamy yellow, with pink tips to the shoots, and the whole plant becomes tinted in pink and then burgundy in cooler weather. What’s more, there are also spikes of small white flowers in summer. Makes Hebe ‘Pink Elephant’ a very attractive individual specimen. Best in sun. Hardiness rating H4.

Impressive fragrance

Daphne × transatlantica Eternal Fragrance (‘Blafra’) produces pink-flushed, highly fragrant flowers from April to October

Impressive fragrance, neat, semi-evergreen growth and white flowers with pink tubes make Daphne x transatlantica Eternal Fragrance (‘Blafra’) a valuable shrub but it also has the rare feature of producing flowers not just in the shoot tips but from the leaf joints of the new growth to extend the season from spring into the autumn. Ideal in a prominent sunny position for both flowers and fragrance. Hardiness rating H5.

Japanese charm

A medium-sized deciduous shrub, arching in habit, with deep reddish-purple leaves divided into 7-9 narrow, deeply incised lobes

Many of the smaller Japanese maples are good in containers, in spite of hating prolonged dry summer conditions. The leaves of Acer palmatum ‘Crimson Queen’ are very finely cut to create a lovely lacy effect but its special feature is that, unlike most deep red cutleaf maples, it keeps is colour from spring until the leaves develop scarlet tones in autumn. Best in light or partial shade. Hardiness rating H6.