Jo Arnell finds plenty to look forward to as the season turns

From where I’m sitting on the parched and dusty plains of this summer, I have to tell you that I am pinning all my hopes on September. I’m hoping that September will be the new July, my second chance in the garden. The borders could be as packed with interest and colour as they were back then – in theory.

The days are shortening by the minute (two minutes each day to be precise), there’s a poignancy in every sunny afternoon and the cooler dusks and dawns are dew drenched and cobwebby. But who knows? We might not get a frost for months yet. Let’s seize these golden days and enjoy the jewel-box dazzle of dahlias and rich-hued daisies, the soft light touch of grasses and airy annuals. With luck – and a few tweaks and plant additions – we can keep the summer going for several more weeks.

Late bloomers

Rudbeckias, Echinaceas, Asters and Heleniums are at their best this month. The range of colours is good. Some are autumnal – shades of dusky pink, mellow oranges, rust and mahogany, but there are also bright splashes of blue, mauve and pink from asters.

Plants in the Compositae (daisy) family are packed full of nectar, so will attract butterflies and bees. Some have long lasting seed-heads too; once the flowers have finished they persist as silhouettes, looking artistically sculptural. Their hollow stems make cosy over-wintering homes for ladybirds and other beneficial insects too, so don’t be in too much of a rush to cut them back at the end of the season.

The flowers of Sedum spectabile are also a magnet for butterflies and bees. They are a great addition to the front of the border and will provide long-lasting colour right through the autumn too, as the nectar-filled flowers fade into attractive seed heads in shades of russet and bronze. Sedums are easy to care for and will grow in most soils, but given a choice they’d prefer sunshine and free draining conditions.

Annuals

You can’t beat annuals for long season flowering. This is down to their short, but action-packed lives. They only have one season in which to grow, flower and set their seed. If you can thwart them in their life’s purpose by continually dead heading, they will keep trucking along, flowering until the frosts. You’ve got to admire their persistence, but you’ve also got to be persistent yourself – the minute you stop picking they will have crossed the finish line, achieved their purpose and will not flower again. Floriferous and reliable annuals include Cosmos, Antirrhinum, Cleome and Zinnia for sun, and Nicotiana, Mimulus and Impatiens for the shadier parts of the garden.

Tender and short-lived perennials

Dahlias are good value and their large and repeat-flowering blooms make them ideal as cut flowers too. There are lots to choose from – please don’t feel you have to stick to the garish end of the colour range. There are sultry, dark beauties like ‘Arabian Night’ and demure whites, peachy-creams and pale petalled pinks. The flower shapes vary too, ranging from small pompoms through to giant spidery cactus types. Dead head them regularly to keep the flowers coming and then, once the frost has cut them back, either lift and store the tender tubers somewhere frost free for the winter, or (and I did this successfully last winter) take a gamble and leave them in situ, under a warm duvet of straw and mulch. What they don’t like (and let’s face it who does?) is prolonged wet and cold conditions. This eventually rots the tubers, so keep them dryish and unfrozen.

Umbelliferous plants (those in the carrot family) are elegant additions to border schemes. Many are light and airy, some have graceful ferny foliage, all have wonderful flat-headed corymbs of flowers that are wildly attractive to beneficial insects and pollinators. The other good news is that after they have flowered, their seed heads look just as magical. Many will self-seed prolifically too and save you the trouble of growing new plants. They can be annuals, biennials or short-lived perennials. I’m not sure I’d recommend Cow parsley for the garden, beloved as it is at flower shows; it looks delicate and dreamy, but it’s a thug in a lacy outfit, taking over like the weed it really is and self-seeding everywhere. Try the tamer Anthriscus ‘Raven’s wing’, Ammi majus, or bronze fennel for similar effects and sturdy seed heads.

I can’t go on much further without mentioning one of the most ubiquitous, but best loved and constant companions in my garden: Verbena bonariensis. I do take it for granted and it is occasionally irritating (as the best of friends can be), but this is mainly down to its enthusiastic self-seeding habit. It is always forgiven, because it flowers non-stop from June until the frosts, its tall, luminous mauve flowers attracting butterflies, bees and even blue tits along the way.Grow somewhere open and free-draining and it will quickly proliferate.

Super grasses

Many of the ornamental grasses will be flowering around now, sending up shimmering golden, silver or russety flower spikes. Some are demure and ‘grassy’, others show off with dramatic plumes. There are tall grasses that will do the job of a shrub in the border, bringing instant height and presence, but in a more graceful and airy way than a blobby bush. Miscanthus zebrinus, or M. ‘Silberfeder’ are good shrub substitute grasses. Calamagrostis ‘Carl Foerster’ makes a tall golden pillar and will bring rhythm and punctuation to a scheme, while the low growing evergreen Stipa tenuissima is an airy and irresistibly tactile little grass for the front of the border. Grasses last for a long time (most will stay standing right through the winter) and bring movement, texture and drama to a scheme. The trick is to grow them so that the autumnal sun, which hangs lower in the sky and slants at an angle, is behind them. The golden light then shines through and silhouettes the outlines of perennial stems and seed heads against the grasses.

Late summer shrubs and structure

Shrubs provide height and presence, acting as the backbone of the border and there are some great late summer flowering ones that have their starring moment right now. Hydrangeas have long-lasting bracts that fade beautifully into autumnal shades, Hibiscus will provide an exotic boost in shades of pink, blue or white, and the Buddleias bring in butterflies and bees. Smaller shrubs are useful in the middle of the border. Caryopteris has small sky blue blooms. For the front, low growing Ceratostigma willmottianum, with cerulean blue flowers highlighted among deep red and russet leaves is hard to beat.

I’ve changed my mind while writing this. September can never really be the new July, no matter how much I would wish it, the light is all wrong. The earth is turning away from the sun and there is an inevitability about the change of season. But while summer’s passing is always poignant, I hope that along the way we’ve discovered that September’s borders can be just as brimming with life and beauty as they were in earlier months. Let’s stay out there.

Contact Jo on 01233 861149 for details of her courses and workshops hornbrookmanor.co.uk

Cotoneaster horizontalis

Cotoneaster horizontalis

Early autumn at Great Dixter

Early autumn at Great Dixter

Teasel seed head

Teasel seed head

Dahlias come in many varieties

Dahlias come in many varieties

Nigella seed head

Nigella seed head

Amni Majus seed head

Amni Majus seed head

Mop head Hydrangea bracts

Mop head Hydrangea bracts

A classic spikey dahlia

A classic spikey dahlia

The colours of late summer

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