In season

With the weather a mix of summer’s last heat and autumn’s damper notes , Neil Ross suggests marking the transition by devoting a garden corner to the classic colour combination of yellows and blues Yellows and blues are two complementary hues that bring

Neil Ross on complementary hues: yellows and blues

Opposite on the colour wheel, yellow and blue always make each other sing when placed together.

While yellow is forthright and warm and pushes forward, cool blues pull back – drawing the eye deeper into a scene. It’s a ying-and-yang, sweet-sour sort of set-up – opposites creating tension and excitement for the eye.

Yellows are still easy to find in the April garden – mainly from within the daisy family, which are so generous in their flowering. So don’t be snobby about this cheerful colour; go out and grab a pot or two of gold.

The secret with contrasting colours is to team strong hues with strong and the keep the softer, pastel shades grouped together too.

So if I was doing a bright-coloured border, my main dollop of brassy sunshine might come from that indomitable daisy

Rudbeckia fulgida var. sullivantii ‘Goldsturm’, which goes on for even longer than it takes to say its tongue-twister name. I’d put this alongside an equally punchy blue such as Salvia patens, which isn’t too high and could be weaved in among the daisies.

Salvias, along with monkshoods (aconitums), are about the best source of blue in the late-summer garden but take care with using the latter because of their deadly toxicity.

If your taste is for a softer scheme you could get in the tall and softer lemon perennial sunflower Helianthus ‘Lemon Queen’, which flowers for ages and would be a perfect partner for a sky-blue sage such as the bog sage ( Salvia uliginosa), which again matches its partner in stature. These plants can lack much solid shape so don’t forget to throw in some gutsy plant shapes too, such as silvery cardoon thistles (cardunculus) with their bold leaves, or even a sword-leaved agave if you want to tip over into a tropical vibe.

Nothing beats a firm ball of clipped topiary to add some form and structure to a planting. Just a hummock of blue hebe or fading lavender would even do the trick in some places so long as you plant a few for effect.

As well as complementary colours if you can contrast the flower shapes too then you instantly up the ante. For example picture the thin spires of veronica with the ball flowers of rose or a late yellow dahlia.

In similar fashion but a little lower you could try the vertical spikes of the Salvia nemerosa cultivars and throw in strong, contrasting horizontals of a yarrow such as Achillea ‘Moonshine’ or ‘Hella Glashoff’

The key to having plenty of colour in autumn is proper deadheading for key flowers after their first flush back in December. For some, such as marguerite daisies, it’s just a case of neatly snipping off individual heads as they fade all through summer. For the likes of Salvia nemerosa, pale yellow anthemis daisies and veronicas, they need to be snipped off just below the whole flowerheads leaving a stalk that will obligingly sprout new mini flowers a few months later. Other plants such as achilleas and delphiniums need a clean cutting of everything at the base and then they send up completely new flower spikes – especially if you give them a boost with a feed and plenty of water.

The secret is knowing which plants will rise again from the ashes. Few geraniums, iris or lobelias will repeat flower if you cut them back no matter what some books or enthusiastic plant labels might claim but sometimes it’s still worth doing the job just to keep them tidy and to elicit a new set of fresh leaves.

Of course too many perennials in the mix can leave your garden a bit bare through winter so be sure to include some evergreens or at the least interesting seedheads from plants such as miscanthus grasses or the yellow Clematis tangutica ‘Bill MacKenzie’, which pumps out clouds of silky seedheads that are beautiful when they catch the light.

Shrubs give a good bit of backbone even if they are not always evergreen. I grow ceratostigma for its long period of flowering but I enjoy too its airy presence in winter when each twig ends in a nutty cluster of seed. A fat ball of evergreen golden foliage is the cheat’s way to add colour – Choisya ‘Aztec Gold’ or Acanthus ‘Hollard’s Gold’ would be classic show-offs but you would have to live with their unrelenting gleam all year. With coloured foliage my take is definitely ‘less is more’ so I plump for deciduous perennials with fancy foliage so I can take a break in winter.

Many perennials come in goldleafed forms these days and two of my favourites are golden tansy ( Tanacetum vulgare) and golden meadowsweet ( Filipendula ulmaria ‘Aurea’), which stay fresh-looking for a long time.