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Bulbs don't just provide us with spring flowers, but also provide plenty of beautiful blooms for your garden throughout the summer.

Summer bulbs also include plants with tubers and corms. Many corms will eventually clump and spread throughout your borders, repaying a small amount of effort in the spring with flowers all summer and through into the autumn. However, some summer bulbs and tubers are not hardy, so need to be lifted before the first frost and stored, ready to be replanted the following spring.

What to grow


Perfect for a cottage style garden, these tall showy plants look stunning at the back of a border. Corms can be planted directly in the garden from May to July, and some varieties can reach around 1.2m (4ft) tall, so will need to be staked, or planted in a sheltered position alongside a fence or wall. Unless you're in the south of the UK it's best to lift and overwinter the corms. Try the coppery coloured Gladiolus 'Bimbo' for an unusual burst of colour, or a close Gladiolus relative, Acidanthera Murielae, which has delicate drooping white flowers with purple centres and a lovely scent.


The allium family includes hundreds of species, including cultivated onion, garlic, scallion, shallot, leek, and chives. Ornamental alliums have spherical blooms on slender stems, followed by architectural seedheads. Flower sizes range from just a few centimetres to over 20cm, and the pompom flowers come in beautiful shades of purple, pink and white. Use large groups of alliums to add structure to your borders. Plant in well drained, sunny spots or even in pots in a courtyard garden. Try Allium Christophii for huge, globe-shaped, flower heads.


These fast growing corms will quickly multiply in garden borders. From clumps of sword-like leaves, upright arching stems carry flowers in fiery shades that open in succession. Most are orange, but there are also yellow- and red-flowered cultivars, and some with bronze-tinted foliage. Coming up in late summer, they provide interest through to early autumn. They prefer full sun, but do best in soil that retains some moisture in summer, and will tolerate dappled or light shade. Try the RHS Award winning Crocosmia × crocosmiiflora 'Babylon', which has sprays of large orange-red flowers with a dark ring around golden yellow throats.

Bearded Iris

There are a few different Iris, but bearded iris (Iris germanica) is arguably the most popular and is among the easiest to grow. Note that these plants are toxic to dogs and cats. Unlike other bulbs, iris tubers like to be planted in sunny areas close to the surface of the soil. The tubers produce classic cottage garden-style flowers among strap-like foliage. Try "Ice Pinnacle", a lavender/white bearded iris, with white standards and lavender blue falls, flowering early in the season.


If you're looking for a cut flower, dahlias are showy and distinctive with a range from vibrant colours to understated pastels. Dahlias are drought-tolerant plants that will flower long into autumn with regular deadheading.

Buying Bulbs

  • Buy dry bulbs when they're as fresh as possible. Summer bulbs are usually on sale from early spring onwards, when they're dormant.

  • Healthy bulbs will feel firm and show no signs of mould or damage. Look for bigger bulbs as they'll produce bigger blooms.

When to Plant

Summer bulbs such as alliums, agapanthus and cannas, should be planted just as the weather and the soil starts to warm up in spring. As a rule of thumb, most bulbs should be planted at 3 times their depth.

The ideal soil temperature is 13°C as in colder soil bulbs will not start to grow and may rot. Aim to plant dry bulbs directly after purchase. Bulbs you have stored over winter should be planted at the end of their dormant season.

How to plant

Different bulbs need different soil types but summer bulbs generally like a warm, sunny position. Free-draining soil is important as bulbs are susceptible to rotting.

If you have heavy, clay soil dig in one to two buckets of coarse sand per square metre. Adding well-rotted organic matter will also improve drainage.

Dig individual holes for each bulb or a trench for many bulbs. Place bulbs in the holes without pushing down hard. Make sure the growing point is pointing upwards, cover with soil and firm.

Pot-grown bulbs can be planted directly in their desired position in a border - planting 'in the green'. Make a hole wide and deep enough to allow room for the roots to spread and plant the bulb at the same depth as before.

Many summer bulbs are ideal for growing in containers, especially tender species that you need to lift and store over winter. If you're planting in a pot, use the bulb as a guide and plant it two or three times its depth, spaced approximately two to three bulb widths apart.

Lifting and storing

Most summer bulbs are not hardy so need to be lifted before the first frost. Bulbs generally prefer to be stored dry.

Remove loose soil, carefully pull or cut off dead and dying leaves and leave to dry overnight. Dusting with fungicide will help keep the bulbs healthy. Store the bulbs in dry paper bags or trays of almost dry sand in a frost-free place.

A few bulbs need moist conditions and can be kept in slightly damp bark chippings.

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