Drawing clouds and skies can be seen as either difficult or boring when working on a landscape in coloured pencils. Covering a large area with a pencil tip with the intention of creating a smooth surface with no white paper speckles destroying the illusion can seem problematic.
Instead of spending hours blending and burnishing why not employ some of the suggestions below.
One problem with using coloured pencil is that it is a linear medium, designed to produce a line, and a line is not always what you require, especially when drawing clouds and skies.
One technique to get around this is to transfer the pigment to the paper by means of an intermediary. In addition to skies and clouds this is also a good way of creating smooth water and out of focus backgrounds.
This method relies on you making up a 'paint box' or palette, on fairly rough watercolour paper by working areas of very strong colour from your pencils. The paper needs to have a good tooth so that you get a thick layer of pigment to work with. With a piece of white felt or similar fabric, you can then transfer the colour from the palette to the felt and gently rub the felt over the sky area of your drawing. This transfers a thin layer of pigment onto the paper. The darker the colour the more obvious the transfer, with lighter colours you may need several coats.
In the example above Peter used a Polychromos Ultramarine which went down with a relatively light result. He then refined the detail with a Light Ultramarine pencil which was very close to the resultant transferred pigment and blended well.
Because the pencil pigment has not been impressed into the paper in any way, it can be lifted easily with an eraser to show woolly white tops to the clouds. You can also re-work the clouds if your first attempts have not left them big enough.
Why white felt? Well if you have used it in the past for perhaps a grassy field, you will be able to see that green and pick a different area with which to work your sky and avoid contamination. Reusing the same section of felt that has previously been used to create a sky seems to work better and better each time.
Ideally the felt needs to be reasonably substantial, a thin piece will break up more quickly with the rubbing involved. I have found an ideal source in the felt pad of a replacement ironing board cover.
This technique is also great for backgrounds where the area behind the main subject needs to be out of focus If you do this blurred area first, you can erase up to the edge of the subject and then work your detail.
If you are working with a soft surfaced paper, like Stonehenge or Canaletto Liscio, the surface can be lifted slightly by the rubbing action, so more care will needed. It isn't usually a problem with ordinary Hot Press watercolour papers like Fabriano as they have quite a hard resistant surface. If the surface does start to lift, then a burnish with a white pencil can often apply 'first aid'.
If you are erasing surplus pigment from the surface, always work with a clean eraser and from 'within' the area you will want to apply detail to. For fine work it is best to use a battery eraser or Tombow type eraser, as these have a narrow point and can be more accurate.
Using watercolour pencils the task of drawing clouds and skies becomes easier, quicker but more random. Some would say challenging, but then we all like a challenge, eh?
If you are using stretched Hot Pressed watercolour paper of around 300 gsm (140 lb) weight then the operation is a simple one of getting the paper thoroughly wet in the sky area. We don't need to worry about overlapping distant land with blue sky as the blue pigment will not be strong and it will provide a good distant blue underpainting for the far parts of your landscape drawing.
If you are starting from scratch and don't want to stretch paper, then I recommend using a heavier weight paper (425gsm or 200lb) which will take the water treatment without buckling.
You will also need a piece of rough watercolour paper, as above, to act as a palette and hold the dry pigment.
Lay down a substantial layer of clean water over the sky area of your paper and let the paper absorb some of this water for a few seconds. Check that there is still a glisten of water visible on the surface and then pick up a dab of Ultramarine Blue from your palette onto your brush.
Peter finds Ultramarine Blue the best of the blues for this, but obviously skies around the world differ, so you may need to practice. Bear in mind that the darkest blue will be overhead and the sky on the horizon will be much paler.
Tilting the board and pushing the blue pigment with the tip of a small brush lets the water on the paper surface work its magic in moving it about. In the example above Peter encouraged the blue to travel across the paper in lines. Some areas are darker than others and later in the development of the drawing, he worked some of that same blue pencil dry, to intensify one or two areas of the sky along with warm grey shading to the base of the clouds.
In this picture a lot of the sky will be covered with tree foliage so the branches and leaves will be worked before the sky is tinkered with at the end.
As the finished picture shows, not a lot of blue sky is visible through the trees, but you are aware that it is there.
The rest of this picture of an Australian landscape was completed in Derwent Watercolour Pencils used dry, which gives us the lines of grass and the detail of the tree foliage.
Below are three further examples drawing clouds and skies with watercolour pencils.
Remember to graduate the colour of your skies. The density of blue in the clear unclouded sky changes from a deeper blue overhead where there is little dust in the atmosphere, to a paler blue as the sky is seen near the horizon where dust particles obscure the colour.
This is known as Aerial Perspective, where the dust reduces the crisp definition of distant scenery and also cuts down the depth of warm colours seen at a distance.
Make sure when drawing clouds remember where you want the direction and position of the sunlight (if any). The opposite side of a cloud to the sun will have shadowed areas - usually below centre unless it is evening, in which case your clouds may be in direct shadow with the lower sun directly behind them.
Look at clouds and skies in real life and maybe take some photos to build into your own personal library. In the meantime look at the photos below.
As you can see from the few examples above, skies come in a range of blues, and clouds come all colours - especially at sunset (though I must say I have never seen a green one).
Remember when drawing clouds where you want your light to come from within your picture (for shadows etc), and make sure that your invented clouds have the same lights and shades in the right positions.
Because mixed media is now becoming very popular and pastel options have widened with the arrival of Pan Pastel on the market, we must also consider how skies can be introduced to our pencil picture using fixed pastel.
Wax pencil works very well over the slightly granular surface of fixed pastel. It can also be used over unfixed pastel, however. The pastel does not have to be the relatively expensive Pan Pastels. You can also use hard pastel sticks to put down a light colour covering and then erase the clouds.
The picture below used Pan Pastels for the background with wax pencil on top. It shows mist in Ilfracombe harbour (UK).
The landscape drawing below, of a UK Lake District Farmhouse used stick pastels for the background. I think this is one of my favourite of Peter Weatherill's landscapes.