The study of colour is a massive science. We have cones in our eyes that interpret colours. We have 3 primary colours from which all other colours are created. How we interpret a colour can vary greatly depending on what other colours we see at the same time, so hot colours can be cooled down with blues, etc. But let's not get bogged down in too much science.
Colour Wheel Theory :
Contrasting Schemes : Pick a colour you like and the opposite colour on the wheel will be a good contrasting colour.
Harmonious Schemes : Pick a colour you like and the colours on either side will be good for creating a harmonious mix.
I don’t use the colour wheel in this way so much. Instead I focus on the intensity or colour depth. See the rings around the wheel showing the colours intensifying with colour saturation towards the outer circle? Simply put, I match strong colours with other strong colours. Pastels with other soft colours. It never fails and I highly recommend it. So let's take a quick look at this.
Strong violet blue and orange have always been good bedfellows and sit opposite each other on the colour wheel, but the intensity of the pink matches the intensity of the other two and makes this composition so much more dynamic and modern. Pink and orange would not be obvious companions, but this really works and relies on matching the colour saturation depth. A pale shell pink would really not work with the orange. Because of how our eyes interpret colours adding in something not tonally correct alters the ‘temperature’ of everything around it. Therefore, a cool pink would jar with the heat of the orange making it garish looking and cooler, in addition to also removing all warmth from the blue. However, the intensity of this pink adds more heat and vibrancy to both and subsequently adds more interest. If you were to add white or yellow to this composition it would break it and I talk about these two particular colours in more detail later.
I do have some hard and fast rules for my garden designs, but as colour is hugely subjective to personal taste, do feel free to do your own thing.
Rule No. 1 – Be careful with White.
I love using white flowers, I like them in early spring as they feel like a gentle awakening from a deep sleep. I like using them with soft lilac’s, lemons, mint greens, pale blue’s and blush pinks. Whites are useful for breaking up blocks of soft colours and transitioning between them. They add freshness and light and are absolutely my No.1 choice for deep shade because of their ability to disperse the gloom. However, due to how the cones in our eyes perceive colour, whites dramatically alter the temperature of what we see. Meaning it can really dilute and weaken strong, hot colours. I think mingling whites with hot colours smacks of the garden centre variety bedding planting style of 70’s gardening. Just because they still sell it doesn’t make it right! The only time I will ever break my rule and use a white with a strong colour is in a minimalistic style of planting. White with a vivid raspberry for instance, and I would only ever do it if the overall palette will be kept very strict.
Take a look at the picture below and think how much stronger this composition would be if the white had been planted with tangerine orange or a pale pink even a lemon yellow would have been good here. For me, the white totally pops out and dominates.
Rule No. 2 – Yellow needs to be Mellow.
An astonishing amount of yellow flowering plants fall into the acidic yellow hue. Acidic yellow is a sharp, cold, garish yellow very difficult to integrate. They have a very cheapening effect on hot colours. Again, it’s my aversion to 70’s style planting of ‘all colours everywhere’ mentality, which is still so prevalent today. There are lemon yellows, with a very soft colour depth which look great with whites and light pastels (not always great with pink). And there are good rich, buttery and burnished golds and yellows, which do well with hot colours particularly deep plums and this is where I really pay attention to colour depth saturation. Yellow can be tricky in other words, use with caution. A common culprit of acidic, neon yellow is the much loved daffodil.
Rule No. 3 – No strong colours in shade
This one is a personal one for me. I find reds become muddy brown in darker parts of the garden and plums and strong blues just disappear altogether. Deep shade needs to be broken up with whites and other light colours. My rule of thumb is the stronger the colour the more sunlight it needs. The intensities need to be matched. In East facing parts of the garden that get weaker morning sunshine, or dappled shade gardens, I keep the palette cool and light and save the bolds and the vibrants for the South and West facing borders where sunlight is stronger and longer.
Rule No. 4 – Lime Green needs to be seen.
As a self confessed plantaholic, I actually still struggle with this one myself. But experience and discipline have taught me that lime green foliage plants create a magical alchemy in the garden by creating a neutralising effect. They act as ‘bridging’ plants that bring most combinations together. In interior design, touches of black or white in a room act as anchors to make other colours 'true'. In the garden, lime greens serve the same purpose. A cool and calm colour palette with lime greens added will enhance the coolness, lushness and freshness. Added to a hot colour scheme it links well to stop it looking crazy and unplanned and most importantly really lets their vibrancy sing. Mother Nature knows her stuff. This means bold planting schemes tie together and have cohesion, no matter how zany the colour mix.
I know. I know. It's still tempting to only want to fill your garden with glorious flowers. However, think of a bouquet of flowers from a florist versus a bunch of flowers from the 24 hour garage. There may be 12 blooms in each but the difference is there will be no foliage mix in the garage flowers. Flowers need great foliage to really set them off to their best advantage.
Three of my favourite Lime Green Foliage plants :
Left, Euphorbia Oblongata. Good in sun and part shade, fantastic planted among spring flowering bulbs like tulips, and great for vases.
Centre, Euphorbia Robbiae. Simply the freshest 'limest' green available for shade.
Right, Alchemilla Mollis. I love this plant as it thrives in all conditions and is tough as old boots and I use it everywhere.