The Problem: A Bright Sky
In real life the daylight sky is bright, much brighter than the landscape’s trees, vegetation, mountains, and water. Think of it as a large lamp. But when you paint a landscape truthfully the effect backfires, the sky will be bright but the earth part will be dull and muddy. Light on the green trees, stone buildings, and red flowers can’t complete with the sky’s light. Even though you are seeing a sun filled landscape, your painting won’t feel that way, but you’ll feel disappointed with your skills.
Picasso says “Art is a lie that makes us realize truth.” Using this trick, paint the sky not as bright as you see it, but paint it pale with dull medium tones. You will accomplish two things: the diminished light of the sky will set the sky back further in space, and you will have a greater range of middle to light colors to give the effects of light on the ground, mountains, and vegetation. Notice how Monet does exactly this in the painting above.
I have done a similar thing with this pastel above of a California high desert.
Abiodun Olaku solves the sky problem in fascinating and realistic way. Many of them are not painted in daylight, rather he paints dusk and dawn with a smokey sky holding an echo of the light that was or a promise of the light to come. The sky becomes dense enough to serve a supporting role for all the man-made lights.
The best setup for creating light in your landscape painting is to turn off the light in the sky, in that way you tell a little white lie that gives truth to your perceptions.