Jo Arnell celebrates the joys of myriad colours in the garden

I spend a lot of my time adding structure to gardens – trees, shrubs, evergreens and architectural foliage plants. We need these to give our borders cohesion and good overall shape, to act as backdrops and frames for the seasonal plants as they come and go. Structure is sensible and important, but without colour there’s not much joy – it can seem like an empty stage waiting for the action. It could be a floaty, soothing blend of harmonious pastels or a riotous clash of the most vibrant and cheerful hues – taste is personal and often idiosyncratic, but whatever side of the colour wheel you roll on, adding a splash (or a flood) of colour will instantly bring a garden to life.

Some effects of colour – and colour schemes

Pale colours recede and make things seem larger or further away. Strong colours are dominant and rush towards us. You can use this to create illusions with space or to play with perspective – make an area seem bigger by using paler plants in the background and brights and darks closer in. Dense, dark colours are sombre, but can provide an anchor point, and make excellent backdrops for other plants.
Pale colours will lift a shady area (as will glossy foliage – it is reflective). Fiery reds and oranges create excitement, whereas pastel colours are calming. The quality of light changes during the day too – whites, pale creams, mauves and blues shine out at dawn and dusk and are ‘washed out’ in strong light, whereas bright colours look best in full sun and fade into the background as the sun goes down.
It’s easy to forget that green is a colour too. In the garden it becomes a calming neutral background, because there’s so much of it around, but its effects are felt nevertheless. Green falls in the middle of the spectrum and is restful to look at – it is the colour of nature and immediately makes us more relaxed (this is why so many hospital walls are painted in soft greens and blues). Whether it’s the darkest shade of holly through acid lime, chartreuse, glaucous, almost blue to pale and silvery, green remains a tranquil foil, harmonising with other shades of green and providing a buffer between patches of colour.
Harmonies are created by using similar colours – pale pastel shades of mauve, blue and pink blend well together and look lovely in semi-shade or the dappled light under trees. Cottage garden perennials like Nepeta (catmint), Geranium ‘Johnsons Blue’, or the longer flowering, but less interesting to pollinators, G. ‘Rozanne’ look romantic under roses. Sunny borders may need to be brighter to stand up to harsh sunlight. Geranium ‘Ann Folkhard’ has magenta flowers with a dark central ‘eye’, Geum like the sun (but also damp soil) and are available in cheerful shades of orange and yellow – my favourite (at the moment`) is G. ‘Totally Tangerine’, which seems to manage and even clump up unusually well in free draining conditions. For a splash of vibrant red you can’t do much better than tall and architectural Crocosmia ‘Lucifer’, which enlivens both exotic and cottage schemes.

Fabulous Foliage

The range of flower colours available to us is mind-blowing, but flowers are fleeting and can’t be used to carry a scheme through every month of the year. Foliage can offer nearly as much variety in terms of colour – and for a much longer period. Leafy plants can have the added advantage of good shape and form too. Foliage can still be a part of colour schemes – picking up the colours and enhancing their effect, or even to carry the scheme once the flowers have finished. A leaf can often have as much colour as a flower, and is far longer lasting. Large leaves and architectural foliage will also bring structure and unity to the border.
Cotinus coggygria (the ‘smoke’ bush – so called because its flowery plumes look puffs of smoke) is a large shrub grown mainly for its leaves. The best known varieties are ‘Royal Purple’ which has deep plum coloured foliage, or ‘Grace’ whose leaves are more translucent and ethereal. Plant Cotinus in a sunny position at the back, or as a specimen – the sunshine will make the vibrant red of the autumn colour stronger.
Berberis is smaller leaved and spiny, with orange flowers in spring, but offers similar deep red/bronze and the deciduous varieties will be fiery in autumn. It’s a big group – a Berberis could be a huge back of the border monster, a diminutive dwarf like B. ‘Nana’, or even columnar – B. ‘Helmond Pillar, ‘Orange’ or ‘Golden Rocket’.
Try the exotic looking Melianthus major, with glaucous, serrated leaves (it will be cut down by the frosts as it is slightly tender, but perks up again in the spring). Euphorbia ‘Wulfenii’ also has glaucous blue/green leaves, but these are evergreen and it has the added advantage of handsome lime coloured bracts in spring.
A useful, if diminutive, group of plants that seem to grow in any situation, including tricky dry shade, are the Heucheras. There is a striking, almost black variety called ‘Obsidian’, several cultivars come in opulent maroon shades, but there are lighter colours too, and for a splash of orange, try H. ‘Marmalade.’

An Annual Blast

You can’t beat annuals for a long and colourful season. Their short, but action-packed lives are focused on flowering. Annuals only have one short year in which to complete their life-cycle. If you can thwart them in their life’s purpose by continually dead heading, they will keep trucking along, flowering until the frosts. Floriferous and reliable annuals include Cosmos – usually in shades of white and pink, but some orange and yellow varieties too, – Antirrhinums that bring a rainbow of spires, and Tithonias and Zinnias that sing out, acid bright in the sunshine. For the shadier parts of the garden, use scented and muted tones of Nicotiana, or low growing Impatiens (busy lizzies)

Colourful Containers

Annuals and tender bedding plants in pots will bring instant colour and impact to key areas – terraces and paving are the immediate thought, but you can even put pots into gaps in the borders, or places where the interest is flagging.
The great thing about bedding plants is that they flower for a long period. Remember to look after them – water containers daily in warm weather and if you planted them up in late spring for a summer long show, the multi-purpose compost only has enough food in it for 6 weeks, so after that they will need a weekly feed of liquid seaweed, or a high potash fertiliser.
Pelargonium are a good old stalwart, but there’s a multitude of container plants on sale right now at the garden centres – choose your colour scheme, but also think about shape. Depending on the size of the container (and in summer try to use larger containers as they won’t dry out as quickly), you will need a tall central plant – an Antirrhinum majus, a tall tobacco plant or spire of some kind will work well, then mid height and with a contrasting flower shape – large flowered like a Petunia or Zinnia and then something to spill over the edges – Nemesia, Diascia or Lobelia, even ivy. The phrase used in container gardening circles (I’m guessing there are such things) is ‘thriller, filler, spiller’ to remind us of the types of plants that make good shapes in a pot.

Seasonal Colour

The quality of light changes through the year – furthest away and weaker in the winter, blazingly close in the summer. The seasonal light of the sun will affect the colour palette of plants too. Pale winter light favours silhouettes and husky shapes. Most of the late winter and early spring flowers are white, yellow or cream to signal more strongly to pollinators in low light. Spring is all new and green, interspersed with fresh blues, yellows and froths of pink. As the light gets stronger and the sun rises higher in the sky, the colours strengthen – to attract in sun-loving butterflies and bees.
Our cottage garden favourites – geraniums, lupins, delphiniums and geum will have finished flowering by July and can also have quite straggly foliage by that time too. Keep the June blooms coming by being ruthless – cut them all back – right down to the ground as soon as they’ve finished flowering and by the end of August they will be back with a repeat show of flowers and tidy new leaves.
During late summer and early autumn the palette changes again as the light softens and sinks lower in the sky. Bring in Heleniums and Rudbeckias in russet, gold and mellow orange, the deep blue of Echinops and brighter hue of Ceratostigmas, Salvias in a myriad of colours and the dusky pinks and mauves of Asters. The flowers of Sedum spectabile are a magnet for butterflies and bees and are a great addition to the front of the border, providing long lasting colour right through the autumn too, as the nectar-packed flowers fade into attractive seed heads in shades of russet and bronze.
Every season brings in a range of different colour choices – I once gave each month a colour (but we know that way madness lies). In the end it will always be down to personal preference – the important thing is to enjoy the colours of your garden, calm harmony or riotous assembly – it’s entirely up to you.

Join Jo for a gardening class at her garden in Woodchurch. Call 07923 969634 or see hornbrookmanor.co.uk.

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