Recently I completed a painting of a moonflower, and I took photos of the process. First I laid down a layer of light green:
This also established the outlines of the white flower. Since the flower was white, I wanted to leave bright white highlights available for the flower's petals, and the only real way to do that with watercolor is to leave highlight areas unpainted.
Next, I needed to establish the shadowy background behind the leaves:
I don't really use the color black in pure watercolor paintings. I don't think it gives the eye enough "life"... it's too much of a cheat, and it's too final. I'm sure that doesn't make sense. Let me take another stab at it. In actual real life, there really isn't much that's truly flat black... even black marker or black crayon is often created by just an over-excess of blue or red or purple pigment. Besides, a viewer doesn't need everything just force-fed. Your eyes need something to do, to make a painting more interesting. You see my final painting of the moonflower, you don't perceive the background necessarily as "purple", even though it really is. You perceive it as "shadow", and your mind automatically classifies it as "black" or "dark" and then no longer considers it.
Next, I need to deepen the tones in the leaves. Again, sticking with only green tones is too easy and deprives the eye of its fun in piecing things together for itself. So the darker areas get some blue:
Deepening those background areas with some indigo tones:
When working with things that are white, you have to remember that there are shadowy areas even on white petals. How to go about creating these? Pale purple. Really. See? :
Details of purple splotches and yellow-green throat:
And then finally, I add some slightly darker gray-green "details" in the leaves to make them seem more nubbly and textured:
I'm actually still learning to do this. It's all a grand experiment, and as often as not, my experiments don't turn out to be blog-worthy, or even light-of-day worthy. But it's all a great exercise in learning to SEE... to see the colors behind the colors, which when layered together give you more than the sum of their parts.
I have more to show you in the upcoming days.