A few weeks ago I received an interesting query about how one determines what colours to use in response to a landscape. I could write a book on this fascinating subject, but I'll try to answer that as best I can in this limited space and perhaps follow it up with an article on the subject later.
In some of the practical art books I read during my early days we were warned against relying too much on the colours in photographs taken of landscapes as the colour reproduction was often unrealistic, and it was best to work from the landscape first-hand to achieve the precise colours in the scene. This approach, however, adopts the premise that we simply want to copy exactly what is in front of us, and to blazes with any of our own artictic creativity. In our paintings we are not trying to emulate photography.
In this painting the topographical features and buildings are fairly faithful to the scene, but the colours could not be much more different to what was actually present on this occasion. I have grossly romanticised the colours with mauves, orange, alizarin and other colours for both sky and land, and created a glimmer on the water. JMW Turner likewise used colour on many occasions for its emotional power, rather than sticking to what was before him, much to his contemporaries' astonishment. Colour is closely bound to mood and emotion, so much thought should be given to your proposed palette before you begin painting.
You may wish to take a less romanticised approach, but even so it is perfectly legitimate to alter the colours from the original scene. Colours are affected by the weather, light, seasons and a host of other factors. For example, one day a field can be a pale green perhaps, and the next when the farmer has cut the hay it can be a distinct Naples yellow. Fields get ploughed up and lighten in tone and colour when the dry out, and I have seen a cottage roof change in brilliant sunshine from black to the most brilliant gleaming whiteness after a shower of rain followed by more sunshine. I often change a field by the centre of interest from a dull green to a shimmering yellow to draw the eye in, and perhaps do the opposite to the landscape at the edges of the composition so that it doesn't draw the eye away from the centre of interest.
Landscapes are commonly overwhelmed with greens, but if you try to copy every green you can see you will be ovewhelmed, and the result can look chaotic. What may look right in reality or a photograph simply may not work in a painting. We need to interpret colour as much as we need to do so with other aspects of a scene. Choose a maximum of three or four greens. Variegate them by dropping in other colours while they are still wet, but also consider changing them for a totally different colour. I've even seen red grasses out there, so you have quite a range to choose from!
OK, but what if you see a colour out there that you really like, and want to replicate? Study it carefully and experiment with as many colour mixes as you can in an effort to achieve a decent result, but you need to do this on separate paper, not on the composition you are working with. If it's still not working touch in a third colour into the mix. Another way is to take out colour swatches of various greens (or whatever colour you wish to relicate) and try to match one as close as possible to what excites you, noting whether it is darker, lighter, warmer, cooler, more or less intense, and so on. Back at home you can then experiment further and study other artists' work to see if they have created a similar colour, and by which mixtures have they achieved the result.
I hope this helps. I've recently returned from Cornwall where I ran a course organised by Alpha Painting Holidays. Matthew not only organised a great location, but also organised some truly wild weather which brought us some amazingly dramatic seascapes with huge breaking waves. It was great fun.
I have a zoom demonstration on Saturday 24th September at 12.30 pm in conjunction with Patchings Art Centre, so do please join us if you can. It's free and will last one hour. I shall be demonstrating coastal scenery, and the link is as follows:
https://us02web.zoom.us/