Thanks to the lingering heatwaves, many gardeners are enjoying an early show of late-summer blooms, writes Hannah Stephenson.

I don't know if it's the same for you, but my late-summer blooms - which traditionally show their colours towards the end of July and August - have already been out for several weeks, brightening the otherwise rather dry and sorry scene in my garden.

Thanks to the prolonged heatwave we've been having, many UK gardens are now bursting with colourful reds, yellows and oranges, as heleniums, rudbeckias and crocosmias come into flower. Meanwhile, hydrangeas, asters, Phlox paniculata and dahlias are all adding to the mix - so if you've also kept your annuals blooming by feeding, watering and deadheading, the garden should be a riot of colour for the rest of the summer.

Among the great late-flowering perennials, here are some of the best late-summer blooms brightening up gardens right now...

1. Crocosmia 'Lucifer'

This showstopper of a crocosmia is taller than many of its relatives, growing to around 120cm (4ft) and producing fiery red-orange flowers against its backdrop of sword-like leaves. It looks great in the late summer border with heleniums and red hot pokers and will tolerate most types of soil, but will need watering and mulching if the soil is very free draining.

Lift and divide the corms every three to four years - and don't let them take over because they can be quite invasive.

2. Helenium 'Moerheim Beauty'

This gorgeous daisy-like perennial produces deep coppery blooms with a prominent central disc which seems to rise above the outer petals when the sun shines from July through to October.

They're a magnet for bees, but do need watering reasonably regularly in hot, dry conditions as otherwise they will flounder. Heleniums do best in rich, fertile soil and are a good choice for clay soil. The beauty about this variety is that, unlike other heleniums, it doesn't require staking. Deadhead regularly to keep new flowers coming. They look wonderful with ornamental grasses or bold foliage plants.

3. Phlox paniculata

These gorgeous puffs of white, pink and mauve look fabulous in the late summer border in a moist but not waterlogged soil, and prefer either sunny or partially shaded beds.

Bees and butterflies love them and they are most impressive in drifts in the middle of borders, to provide pools of summer colour. Plant ground cover, such as small asters, in front of them to hide their bare stems.

4. Michaelmas daisies (Aster)

Asters, the daisy-like stalwarts which come in a range of blues through to white, may not be everyone's choice because they do self-seed and can be invasive, but I love a good clump of any of the white varieties, which provide a valuable cooling note to the late-summer border.

Among the most popular is A. x frikartii 'Monch', which bears lavender-blue flowers from July to October and grows up to 90cm (3ft) tall. White options include Aster novae-angliae 'Herbstschnee' and Aster ageratoides 'Starshine'.

5. Tree lily

These late-summer flowering giant ornamental trumpet lilies look - and smell - amazing. Majestic, standing tall at the back of the border, above the other perennials, some grow to around 2.5m (8ft) in just a couple of seasons, providing stunning colour and scent.

Each bulb of the tree lily 'Yellow Rocket', for example, produces up to 30 saucer-shaped blooms with a white edging and soft yellow centre, while the thick stems don't need staking. Grow them through shrubs in borders, or against walls or fences.

6. Rudbeckia 'Goldsturm'

These vibrant yellow sizzlers, with a dark-eyed central cone, look amazing in a border, their large daisy-like flowers attracting bees and butterflies and partnering well with deep orange-hued rudbeckias and other late-summer blooms.

These perennials grow to around 60cm in height and form clumps, with erect stems bearing the flowers which can last until autumn. They do best in full sun or partial shade in moist but well-drained fertile soil.

7. Hydrangea Runaway Bride 'Snow White'

Winner of this year's RHS Chelsea Flower Show Plant of the Year, this white beauty flowers not only from its terminal buds as with traditional hydrangeas, but also from virtually all the lateral stem buds.

Flowering from late spring/early summer well into autumn, Hydrangea hybrid Runaway Bride(R) 'Snow White' produces a profusion of lacecap white flowers flushed with pale pink - often six along each branch - on graceful, trailing stems.

Neat, compact and hardy, it looks lovely in patio containers or mixed borders. Height and spread 120cm (47in).

8. Agapanthus (African lily)

Traditionally blue or purple, these beautiful perennials with showy flowers and strappy leaves also come in white and pink.

They thrive in well-drained soil in a sunny spot in the garden, and also do well in containers. Flowering until early autumn, they will benefit from a dry mulch of sand or straw over the winter.

Bring potted agapanthus close to the house in the colder months, or ideally put them in a frost-free greenhouse, as some are hardier than others. In borders, they are ideally matched with other blues and purples including salvia and lavender, or in a striking clash with orange crocosmias and red hot pokers.