Posted on May 14, 2018
Sap Green is a generic name for a warm, deep green. Perhaps its difficult to tell, but the above detail of a portrait painting was made possible with the invaluable Sap Green and even though impossible to see really its all over it! Sap Green cools reds. Red and green are complementary colours so together they neutralise each other. People generally aren’t that green, but they are greener than you might imagine.. skin in shadow is invariably greenish in hue. Maybe greenish is too strong a word (it might not be a word) but generally when I paint shadows there are always greens silently working their magic.
There a lots of different Sap Greens made by different oil paint manufacturers as each develops their paints in their own way. I love Michael Harding’s oil paints and I love his Sap Green, but it doesn’t have the particular warm quality I am generally after when I reach for it, in the context I want it. It is good for cooler shades and hues but I haven’t yet been bold enough to use it in a portrait. Michael Harding’s website says that it would be ideal for the plein air painter which is true.
The Sap Green I worked with when I studied with Louis Smith was one of the warmest greens I had painted with (Lukas studio oils), and I discovered mixing with Alizarin Crimson is brilliant for cooling down reds in shadow tones. It served this purpose in the portrait painting shown. I painted this shortly after I did a glazing workshop with Louis Smith in Manchester and it was a revelation for me. The sap green I generally use is the Winsor and Newton Winton variety, but I’m sure there are a lot of other ones out there including the Lukas one. I have just been going through what I already have in my paints box. I also have an old tube of water-mixable Duo Aqua sap green which I can use as its also warmish.
The one colour I can’t live without at the moment is sap green. What a discovery that was! All credit to Louis Smith for introducing me to it back when I was starting to seriously paint portraits. For me all skin tones seem to flow from there when this green is mixed with alizarin crimson or cadmium red. In my case I generally add both, or start with a dark mix of crimson and sap green. I have found myself recently mixing a deep colour using these two and working from there on the palette in various directions, adding white here, blue or yellow there and seeing where I end up.
If I mix Sap Green and a red for a shadow and it’s still too warm I mix in a bit of blue. It could be any blue but the blue I have on my pallet is Ultramarine. This again is a warm blue, but its cool enough to dampen the fires of Cadmium Red or Alizarin Crimson. I have to be careful not to add too much blue or it overpowers the other colours.
Honestly I think I would struggle to paint a portrait without it these days. The description on the Winsor and Newton website says Sap Green is a bright mid-range green with a yellow undertone. Originally Sap Green was a lake pigment made from unripe Buckthorn berries. Here is a picture of some Buckthorn, also once used as a ‘purgative’ which sounds nice. Perhaps its a good thing its not used anymore as its very toxic.
My palette is a fairly warm one when seen all laid out, and I’m sure at any time I could dispense with some of the colours. I generally don’t use umbers (browns) in my palette except when I’m doing drawing or underpainting. I have found its convenient to have a bit when I’m painting hair, but I usually mix my browns from various other colours, typically starting with a red and sap green together. Here is a video starting at the moment I have prepared a glaze mix on my palette using these colours, and I use it for the hair:
When mixing colours I’m always back and forth, correcting and adjusting as I go. I never get it right first time but have come to see it as a process of guesswork where I try a colour, see it in context, and then try again. I was never taught any formal method like you might see on an academic painters palette. Sometimes when I have a very warm hue for a highlight, where I have used a lot of red, it can work very well to just add some blue or a sharp green like Viridian. I want to try and get the values to remain the same with the two colours, but the cooler hue bounces off the warmer and creates the subtlest shadows. It still takes a bit of time when painting to get to the point where I can find this balance, and often I do it by accident. That is part of the pleasure of painting though, where we are constantly surprising ourselves.