Hot Border Planting Ideas: Reds, Oranges, Golds

A hot border is one of the boldest things you can plant, and it’s easier than it looks. Fill a sunny bed with scarlet, orange and gold flowers, set them against dark purple foliage, and the whole thing glows from June to October.

This guide gives you the plants, the layout and the timings. It sticks to the fiery end of the spectrum. For colour schemes in general, our guide to using colour in garden design covers soft, cool and contrasting palettes, and the colour wheel garden design guide explains how colours work together.

Why hot colours work in a border

Reds, oranges and yellows are advancing colours: they seem to come towards you, while blues and greens seem to sit back. That’s why a hot border looks closer and brighter than a pastel one the same size. Put one at the far end of the garden and it pulls your eye straight down the plot.

Three tricks make the heat look stronger:

• Dark foliage behind. Deep purple and bronze leaves make scarlet and orange flowers stand out.
• A touch of lime. A few lime-green plants, such as euphorbia or lady’s mantle, make red and orange really sing.
• A tight palette. Stick to red, orange and gold with one dark and one lime accent. Add pale pink or soft blue and the border loses its punch.

Where to plant a hot border: sun and soil

Give a hot border full sun, ideally a south or west-facing bed. Most of the stars come from open, sunny places. In shade, crocosmia, dahlias, red hot pokers, rudbeckias and heleniums grow leggy, flop and flower poorly.

They want free-draining soil that holds some moisture in summer but never sits wet in winter. On heavy clay, dig in plenty of organic matter and some grit before planting. Winter wet rots dahlia tubers and crocosmia corms far more often than cold does.

Feed lightly. A spring mulch of compost and a sprinkle of balanced general fertiliser, following the pack, is plenty. Too much nitrogen gives soft, leafy growth that flops and flowers late.

Building structure and repetition

Start with two or three structure plants, bigger shrubs or bold clumps that hold the scheme together all season. Dark-leaved shrubs such as Cotinus ‘Royal Purple’ and Sambucus ‘Black Lace’ are perfect, because they give height and the dark backdrop at once. Space these first, then fill the gaps.

Plant everything else in groups of 3, 5 or 7 rather than single plants dotted about. Odd-numbered groups knit together into natural-looking drifts. Then choose two or three anchor plants and repeat them along the border, so the eye follows a rhythm. For more pairing ideas, see our guide to the best plant combinations for UK borders.

Purple smoke bush leaves make the oranges and reds in front look even hotter. Plant the dark shrubs first.

Layering by height: back, middle and front

Step the planting up in tiers so nothing hides behind anything else.

Back of the border, over 1.2m

The back row carries the height and most of the dark foliage. Cotinus ‘Royal Purple’ and Sambucus ‘Black Lace’ make large shrubs. Cannas add big bronze or striped leaves and orange or red flowers. Ricinus (castor oil plant) grows fast from seed with dramatic bronze-red leaves.

Warning: Ricinus seeds are highly poisonous. Skip it if children or pets use the garden, or remove the flower spikes before seeds form.

Middle of the border, about 0.6-1.2m

This is where most of the colour lives. Plant Helenium ‘Moerheim Beauty’ (copper-red daisies), Kniphofia ‘Tawny King’ (apricot-bronze pokers), Persicaria amplexicaulis ‘Firetail’ (crimson spikes), Achillea ‘Terracotta’ (burnt orange fading to gold), Crocosmia ‘Lucifer’ and Dahlia ‘Bishop of Llandaff’.

Front edge, under about 0.6m

The front softens the edge. Use Rudbeckia fulgida ‘Goldsturm’, orange and gold day-lilies, Geum ‘Totally Tangerine’ and low dahlias. Let a few airy plants drift forward to break up the tiers, so it doesn’t look like a staircase.

The best plants for a hot border

These plants are reliable in British gardens with cool, wet winters. Pick from each flowering period so there’s no gap in the show. For more long-lived choices, see our guide to the best perennial plants for UK gardens.

Crocosmia ‘Lucifer’ is the anchor red: hardy, easy and rarely needs staking. Dahlia ‘Bishop of Llandaff’ earns its place twice, for scarlet flowers and near-black leaves. Helenium and Rudbeckia carry August and September when early perennials fade. Our guide to growing crocosmia covers planting and dividing.

Crocosmia ‘Lucifer’ sends up arching scarlet sprays in high summer. It’s hardy and spreads steadily into a good clump.

Dark foliage and lime green: the finishing touches

Dark foliage is what turns a busy border into a glowing one. Build the dark layer from Cotinus at the back, Sambucus ‘Black Lace’ for its fine-cut leaves, and the bronze leaves of Dahlia ‘Bishop of Llandaff’ and cannas through the middle.

Add a little lime green as a counterpoint. The lime flower heads of euphorbia, the froth of lady’s mantle (Alchemilla mollis) or a few Nicotiana ‘Lime Green’ make reds and oranges fizz. Keep it to the odd plant here and there. Euphorbia sap irritates skin and eyes, so wear gloves when you cut it.

Grasses calm the heat. Stipa and Calamagrostis ‘Karl Foerster’ add movement and soft neutral tones. Their seedheads also stand through winter and look lovely with frost on them.

Dahlia ‘Bishop of Llandaff’ gives you bright flowers and dark leaves in one plant.

Keeping the colour going from June to October

A good hot border never has an off week. That comes from mixing flowering times, not from one show-stopping plant. Think of the season in three parts.

June and early July: Geum ‘Totally Tangerine’, Achillea ‘Terracotta’ and the first red hot pokers.

Mid July to August: the peak, when crocosmia, helenium, persicaria and the first dahlias all flower together.

September and October: rudbeckia, dahlias in full swing, late heleniums and cannas, with the grasses turning gold.

Dahlias and cannas are worth the extra effort. They flower from July until the first hard frost. Our guide on when to plant dahlias covers timing, so they take over as the early perennials fade.

Helenium and rudbeckia together carry late summer, after the early perennials have finished.

Staking, feeding, deadheading and cutting back

Stake early. Push twiggy hazel or metal grid supports in during May, so plants grow up through them and hide the frame. Staking a collapsed helenium in August never looks right. Crocosmia and red hot pokers usually stand up on their own, but tall dahlias, heleniums and persicaria need help in windy gardens. Our guide to staking tall perennials shows the main methods.

Feed lightly. A spring mulch and a little balanced fertiliser is enough for plants in the ground. Dahlias in pots like a high-potash liquid feed, such as tomato feed, every couple of weeks from July.

Deadhead often. Snip off faded dahlias, heleniums and rudbeckias every few days and the plants keep making buds. Cut geums and early achilleas back after their first flush and many flower again in late summer.

Cut back in late winter. Leave grasses and rudbeckia seedheads standing for winter structure and birds. Cut hardy perennials to the ground in February or March, before new growth starts.

Hazel supports put in early disappear as the plants grow through them. Late staking never looks natural.

Month-by-month hot border calendar

This assumes a sunny, free-draining border. Things happen a week or two later in Scotland and the north, and earlier in the mild south-west.

Common hot border mistakes

Forgetting the dark foliage. Hot flowers against a green hedge look flat. Plant two dark-leaved shrubs at the back before you buy a single flower.

One of everything. Single plants dotted about look messy. Buy in groups of 3, 5 or 7 and repeat two or three anchor plants along the border.

Ignoring succession. Buying whatever is in flower on the day gives a border that peaks for a fortnight. Use the table above and cover every month from June to October.

Planting sun-lovers in shade or wet soil. Crocosmia and dahlias in the wrong spot grow tall, flop and barely flower. Give them sun and good drainage, or grow the fussiest plants in pots.

Gardener’s tip: If there’s a dull patch in late June before the main perennials open, sink a potted dahlia into the gap. Lift it out again once the border fills.

Early summer: orange geums and red lychnis start the show while the later perennials are still growing.

Late summer: crocosmia, helenium, rudbeckia and grasses at full heat, carrying the display towards the first frost.

Now you’ve got your hot palette sorted, read our guide on how to plan a mixed border to fit it into the rest of the garden, or find more ideas on the garden design hub.

Frequently asked questions

What colours go in a hot border?

Scarlet, red, orange, gold and bright yellow. Deep purple and bronze foliage make those colours glow, and a little lime green lifts the whole scheme. Leave out pastel pinks and soft blues, which dull the heat and look like accidents among the fiery tones.

Do hot border plants need full sun?

Yes, most need full sun to flower well. Crocosmia, dahlias, heleniums, red hot pokers and rudbeckias all grow leggy and flop in shade. A south or west-facing bed is ideal. Persicaria is one of the few that copes with a little afternoon shade.

Why add dark foliage to a hot border?

Dark leaves make hot colours look brighter. Deep purple and bronze foliage sits back, so scarlet and orange flowers stand out against it. Cotinus ‘Royal Purple’, Sambucus ‘Black Lace’ and Dahlia ‘Bishop of Llandaff’ all do this job. Without a dark foil, a hot border can look busy rather than glowing.

How do I keep a hot border flowering all summer?

Mix early, mid and late flowerers and deadhead often. Geum and achillea start in June, crocosmia and helenium carry July and August, then rudbeckia and dahlias run into October. Deadhead dahlias and heleniums every few days, and cut geums back after the first flush for more flowers.

What is the best red plant for a hot border?

Crocosmia ‘Lucifer’ is a reliable hardy red. It sends up arching scarlet flower spikes in July and August above sword-shaped leaves, and spreads steadily from corms. For a darker look, Dahlia ‘Bishop of Llandaff’ has scarlet flowers over near-black leaves from July until the first frost.

How do you stop tall hot border plants flopping?

Put supports in early, in May, before plants need them. Twiggy hazel or metal grid supports let plants grow up through them and hide the frame. Tall dahlias, heleniums and persicaria need support in windy gardens. Too much nitrogen also gives soft, floppy growth, so go easy on feed.

Do hot border perennials come back every year?

Most do, but dahlias and cannas are tender. Crocosmia, helenium, rudbeckia, red hot pokers, achillea, persicaria and geum are hardy perennials that return each spring. In mild areas with well-drained soil, dahlias can stay in the ground under a thick mulch. Elsewhere, lift and store them frost-free over winter.