I've been having a blast this weekend experimenting with watercolor paints. I have to say I really, really, really like this medium. I've never played with watercolors before now. The closest I've gotten was doing ink washes in high school... which was a loooooong time ago. The best I can tell I'm doing a combination of straight watercolor painting with drybrush elements.
Painting in oil prepared me well for working in this medium. I was able to use the majority of my palette with a few differences. I needed to substitute some paints because of watercolors higher sensitivity to opacity and transparency. Mostly those subs were in the earth pigments which tend to be medium chroma paints. I also had to expand on my oil palette since I need a broad range of chromas in the some of the hue families. A good example is in the 10YR hue family. I went with "Indian Yellow" from M. Graham which is a straight PY110 pigment based paint for my highest chroma. For my mid-range chroma I went with a PBr24 based paint, in this case it's called "Naples Yellow" from M. Graham. This an excellent pigment for my purposes. It's lighter in value than an ocher would be while having the same chroma while also being very opaque. Those qualities I find quite nice for foliage so far. My low chroma/dark pigment is Cyprus Raw Umber Medium from Natural Pigments.
I also found I really needed to expand my dark pigment since washes make up such an important part of watercolor painting. Washes by their nature tend to bring out the maximum chroma in darker paints and I can use this quality to build low chroma tones. These paints are also how I darken all of my higher chroma higher value paints. My list goes like this: 10R - Sepia (PBr7+PBk6) from M. Graham, 5YR - Cyprus Burnt Umber from N.P., 10YR - Cyprus Raw Umber Med from N.P., 5Y - Italian Raw Umber Green from N.P., 5G - Perylene Green (PBk31) from Daniel Smith, 10B - Maya Blue (PB82) from N.P. and Bone Black from N.P. which I put in the 5RP position.
One of the interesting things I've found is I prefer to mix my low chroma greens rather than use something like a green earth or a chrome oxide green. The reason for me is that most of the greens are too high chroma general landscape work or, if the chroma and value are right, they are too transparent. Instead, I use my yellows with black or Perylene Green paint to make dark mid chroma greens. Without the possibility of neutral grays I found this to be the most efficient approach since most foliage moves from yellows in the higher values to greens in the lower values. Between Ivory Black, Perylene Green and Ultra Marine I can control the hue shift as my values darken.
When I think I've got a good handle on what paints I like to use I'll post the entire palette of paints.
Here's a little painting that I didn't get a chance to finish yet... Only got a few hours in before I needed to stop. I'll be adding some dense shadows at the base of the trees and a fence line that also runs along the base of the the trees. You can see the big foreground fence board at the bottom. Kentucky traditionally has these great black fences around their horse pastures.