A couple of weeks ago, I was happily lost in thought over my painting when the ‘phone rang. I still had the best part of the day ahead of me, so I didn’t begrudge this early interruption to my work, but when I answered, I heard a slightly concerned voice at the other end asking me if I still intended to come into class to teach. I had completely forgotten that it was the first day of my new term and I was already half an hour late. To make matters worse, I wasn’t even dressed and the journey would take at least twenty minutes.

A quarter of an hour later, I was in the car and contemplating with a sinking feeling, the effect that being so fabulously late would have on twenty-four students on the first day of a new ‘school’ year. Thinking that I had another week before classes began, I hadn’t done any prep, either. So that’s why I added another ten minutes to my journey to take a detour to a Sainsbury’s store and buy £10 worth of red, green and yellow peppers (and a pack of disposable razors).

Those traffic light colours present an especial challenge to artists and to watercolourists in particular. Peppers are so bright and reflective and their colours so saturated that it’s hard to see their form. Their shadows, in broad daylight, are of the subtlest kind and it’s only too easy to lather on the colour and produce something that looks more like a deformed Smartie than a vegetable. What better way, I thought, to mitigate the awkward start to the new year than with some eye-popping hues and a simple exercise that explores one of the cornerstones of colour theory: complementarity.

Derived from the Latin, complere, meaning to “fill up,” complementarity is used in many different disciplines with slightly different meanings, but we can take it to signify “a relationship or situation in which two or more different things improve or emphasize each other’s qualities” – Oxford Dictionaries website.

The individual qualities of colours and their relationship with others is something that Vincent Van Gogh explored assiduously in his flower paintings, especially:

“At present all goes well, the whole horrible attack has disappeared like a thunderstorm and I am working to give a last stroke of the brush here with a calm and steady enthusiasm. I am doing a canvas of roses with a light green background and two canvases representing big bunches of violet irises, one lot against a pink background in which the effect is soft and harmonious because of the combination of greens, pinks, violets. On the other hand, the other violet bunch (ranging from carmine to pure Prussian blue) stands out against a startling citron background, with other yellow tones in the vase and the stand on which it rests, so it is an effect of tremendously disparate complementaries, which strengthen each other by their juxtaposition.” – Vincent Van Gogh

Flowers are probably a better way of apologizing for one’s lateness.

Begin with a truncated cone to which you add the lobes. You’ll have more success if you arrive at the shape by degrees rather than pitching in with all those curves and creases and skipping the groundwork.

Next, add Viridian or Phthalocyanine Green, but do be sure to leave (or reserve) some paper to create the effect of light shining on the pepper. It’s as well to give yourself a salutary reminder at this point, that in watercolour, there is nothing brighter than the white of the paper that you’re just about  to obliterate.

Once your green is absolutely bone dry, apply an equally dilute glaze of red pretty well everywhere. In the example, I’ve used a combination of Magenta and Translucent Orange, but any red will do the trick as long as it’s not too chalky. For that reason, you should steer clear of the Cadmiums as they’ll probably make your pepper look too muddy.

“Red and green should never be seen,” they say, but in art, they’re such a useful combination. Set side by side, they bring out one another’s qualities and when mixed together, they cancel out and produce colourful darks.

Once the red glaze is dry, add another of green to imply an horizon and bring out the shape of the top of the pepper. A green shadow on the table lends definition to the pepper’s base.

A couple more judicious glazes of red are all you need to complete your pepper, apart from a splash of yellow on the stalk. Reverse the colour applications to paint a green pepper. And if you find yourself on a roll with colour complementarity, try orange over blue and Vincent’s startling citron over violet!