Greens seem to be a difficult color for many painters.  Theories abound on the "correct ways" to paint them, how to mix them, and many other "how to's" about them. I have put a lot of thought and experiment into this family of colors, and here I offer my opinions about them. At the end of this discussion, I offer a tutorial in one method of painting greens that are harmoniously related throughout a landscape. I hope this will prove to be one of the most extensive discussions on painting greens available, and I hope it helps to solve some of these age-old questions.

We'll start with some common questions and concerns about greens.

"Should you use blue and yellow, or a "tube green"? 

This is an age-old debate, and as with most debates, there is no right or wrong. Ask 10 different watercolorists, and you will get 10 different answers. But I have used and tested both methods extensively, and can offer a few guidelines that might help you make the decision.

• First, don't let anyone tell you that either one produces "more natural mixtures", or produces a "greater varitey of greens". You can get just as many natural mixtures and just as much variety with either method. The differences are much more subtle, and come down really to one basic question: "How dominant of a role do greens play in most of your paintings?"

Let's look at the "blue + yellow" method first:

The first advantage, and most obvious, is that you don't have to add another color to your palette to get greens (duh!).

Another advantage of this method is that for someone who uses greens moderately or occasionally, it is usually easier to do it this way. If green is not a dominant color in a painting, then usually one or two good combinations of blue and yellow will get you all of the variety you need. Just put down your blues, put down your yellows, and grab and dobble paint from all the puddles to get your greens.

Also, since most of the tube greens are mixtures of Phtalo Cyanine Green, they are usually stainers. You can make many Blue/Yellow mixes that will lift very easily. This isn't so easy with tube greens. I find that I rarely lift green colors, but maybe you do, so this could be a very important issue.

In addition to these advantages, sometimes you want a green that is on the extreme border of yellow, or the border of blue (in other words, a very bluish green, or a very yellowish green). In this case it would be easier to just mix a couple of blues and add a touch of yellow, or vice versa.

A disadvantage of this method shows up when, like I do, you paint A LOT of greens in one painting. If green is the dominant color of a painting, you run into the paradox that you need variety, but harmony at the same time. What to do?

You may hear the arguement that you can get a wide variety of greens by using 1 blue and 1 yellow, and just varying the proportions of each. This is true, but here is the problem: this is really only 1 "flavor" of green. What I mean, is that you are changing the temperature of the green (warm vs cool), but you are not really changing the saturation (brightness) and other subtle characteristics of that green very much. As for the saturation issue, you may be thinking: "Big deal!". But think about this: what if you are painting a scene that has a whole lot of the same temperature of green, but you just want brighter and duller versions of it? Well, now you will have to mix up at least 2 more blue and yellow mixtures to really get different saturations, and things start to get pretty complicated.

You may wonder, "well why not just desaturate the mixture you already have by adding neutral tint or something else?" Well, you can, but the results will be much duller, with less personality and variation. The reasons for this are many, getting into things like saturation cost, pigment strength, etc. and go beyond this discussion. But trust me, trying to get variation in your saturations by adding a neutral to one blue/yellow mix will not be as vibrant and clean looking as creating a new blue/yellow mix that is inherently at the proper saturation. As an example, mix Phtalo Blue and Cadmium Yellow Pale and you will get a nice bright green. Desaturate it with netural tint or Payne's Gray, and paint a swatch. Now, mix a new green from Cobalt Blue and Cadmium Yellow Medium. This green will be inherently desaturated. I think you will see that the Cobalt Blue mixture, which didn't have to be dulled down by another pigment, is more vibrant and has more personality. And neither of these is nearly as effective compared to using the "tube green" method, as you will see below. Again, this may not even matter to you if green isn't a big feature in your painting. And you might even want it to look a bit more dull. If so, then go for it!

As for the other subtle characteristics I mentioned, that may seem like a detail that you would never notice. But think about this: when you mix Ultramarine Blue and Cadmium Yellow Pale, for instance, you can tweak it both directions as far as you want, but in the end, it will still look like....well like Ultramarine and Cadmium Yellow Pale! Make a mix with Phtalo Blue and Cadmium Yellow Medium and you will get a color that is very close in hue to the previous mix, but it looks VERY different. It is the individual pigment characteristics that bring out the interesting variety. So to get this variety, you really have to make new mixes rather than just lean one blue/yellow mix in different directions. Sure you can add a completely new yellow or blue to the mix you already have. But now your dealing with 3-4 pigments in one mix, and you know that can lead to problems.

And this brings us to one of the limitations of this method: To really get a large variety of greens using the yellow/blue method, you almost have to mix more than just one mixture of yellow and blue. In fact, I would argue that you need at least three mixtures. if you are painting A LOT of greens in one picture, you need variety, but you also need harmony. When you have to use more than one mixture of blue and yellow, you risk losing that harmony, and you risk losing vibrancy and subtle, but important pigment chracteristics. This isn't saying these things are inevitable, but as you will see, with the other method they are much easier to avoid. And obviously, mixing all of these things becomes tedious.

Now let's look at "tube greens":

With a tube green, it is very easy to change the temperature; simply add blue or yellow. Done. What about saturation? Easy: add a compliment or neutral. Done. So look at what this has accomplished: We now have a "home base green" that provides the harmony. We can get temperature changes and/or saturation changes by tweaking it with one more paint, and we've got loads of variation, while still keeping the harmony because of our "home base green". Doesn't that seem simpler?

And what about those subtle pigment characteristics I mentioned? Well now, instead of having to make a new yellow/blue mix every time we want some variation, you just add any pigment of choice to your "home base green", and you've got it. So literally, in one single brush stroke, you can change the whole personality of your green mix, while keeping the underlying harmony there. If you are using Sap green as your base, for instance, in one stroke you can add a bit of Burnt Sienna, in the next stroke add a bit of violet, in the next stroke add a bit of yellow, all of these can be mixed instantly by simply pulling a bit of your Sap Green puddle to the side and plopping in just a touch of your new addition. This can be done very quickly, in a matter of seconds.

Another plus: I mentioned above that when you desaturate a green made from the yellow/blue method, you will possibly create a green that is desaturated, but very dull, with little personality. With a pre-mixed green, I find this problem to be mostly gone. Some may disagree, and in fact, some logic would dictate that using yellow/blue desaturated would have MORE character and vibrancy. But from my countless tests and paintings, I am convinced that tube greens come out on top here. I have lots of theories as to why this is, but again, it goes beyond our focus here. Try some swatches and see: take some Sap Green and desaturate it with Burnt Sienna. Then mix a yellow and blue to get as close to Sap Green as possible, desaturate that with a compliment or neutral. Now paint swatches of these two mixtures side by side. Let dry, and see which one looks the best. My pick every time is the tube green.

This preference is a bit more subjective, but I will mention it: To me it seems that tweaking a tube green without tweaking it too much is easier than using the blue/yellow method. Maybe it is just me, but when I use the blue/yellow method, things start to get homogeonized too quickly, and it becomes harder and harder to change the mix quickly without going overboard. For some reason the tube greens seem much easier to adjust and still keep within a desired range. Try painting at full speed, varying your mixes as you go. First with the yellow/blue method, then with tube greens. Which seems easier to control to you?

So what are the disadvantages? Well, here is another paradox: because of physical attributes of pigments (which are way to technical to discuss here), you usually need a "cool home base green" and a "warm home base green" to be able to get the temperature variety easily and quickly. Why is this easier than just tweaking one "home base green" to very cool, or to very warm? It just is: trust me, I've learned it over lots of painting and experimenting.

You may be thinking this sounds more complicated than the blue and yellow method, but in practice, it's really not. This is because you usally use these different "home base greens" at very different stages of the painting. For example, when painting distant greens, you reach for the cool version, and when painting nearer greens, you reach for the warm version.

Another disadvantage is almost purely subjective but I will mention it, and that is that most tube greens are just mixtures of Phtalocyanine Green and other pigments. Anyone who has worked with Phtalo pigments knows that they are extremely powerful, and require some getting used to in order to use them efficiently and effectively. This can turn off some people. I personally not only have gotten used to the way Phtalo's perform, but rather like them for many reasons.

And since so many of these are made with Phtalocyanine Green, they can be fairly staining. Therefore if clean lifting ability is an issue, this could affect your choice. I find that I rarely lift greens, however.

Some will argue that a disadvantage of "tube greens" is that they do not produce natural looking greens. I think this is an old philosophy that is outdated, and I discuss that below.

"How do you mix natural looking greens?"

I hear this a lot: "My greens always look garish." I think this stems from the fact that our brains tend to want to paint greens brighter (more saturated) than they appear in nature. Many people reach for their bright yellows and bright blues to make a green. These bright greens do appear in nature, but they are not the dominant greens that make up masses of foliage.

If you are using the blue and yellow method, reach for blues and yellows that aren't as bright. Ultramarine Blue, Cobalt Blue, and Cerulean Blue are always good bets. For yellows, reach for the ones that are more toward the orange side of yellow. New Gamboge, Raw Sienna, Cadmium Yellow Deep, and Indian Yellow are sure bets.

If you are using the tube greens, your "home base greens" need to have a saturation like that of most natural greens. The most common, and the one I use the most for my "warm home base green" is Sap Green. There are few other alternatives here. For the "cool home base green", my choice is Viridian. Phtalo Green (blue shade) is also an option. I like Viridian for pigment characteristics that go beyond this discussion.

Now comes a common arguement against tube greens: that they appear unnatural out of the tube. This, to me, is a mute point if you are using them correctly. Yes, if you take some Sap Green and just paint it over a large area, and drop in a few colors here and there, it WILL look unnatural. But that isn't how you use a tube green, or any other green for that matter. As you paint, you must tweak it with Blue, Yellow, compliments, neutrals, etc., just like you would if you were using the blue/yellow method. Just a tiny bit of tweaking as you paint, and I guarentee that your greens will look completely natural. Does this mean that you can't use "tube greens" straight from the tube? No. As long as you are putting down a variety of greens, you can have greens straight from the tube and they will blend in perfectly.

And just for a little tip: a secret weapon for making tube greens look great? Burnt Sienna. Not only does it produce lovely natural greens, but the greens that it does produce have a unique reddish undertone that is inherit in most confierous trees, and is very hard to get with the yellow/blue method. Try it; you practically can't miss by adding this to almost any tube green.

"How do you keep variety in greens?"

This one is simple: Tweak, tweak, tweak! As you are painting, don't let more than a couple of brush strokes go by that you aren't grabbing a slightly different variation of green. Constantly tweak those puddles of color, but not too much that you lose your "home base green". How to do all of this is explained above, and below in the tutorial.

"So what can you conclude from all this?"

In my opinion, if you use greens only moderately or occasionally, go for the yellow / blue method. Also, if you are painting a green that borders on blue or yellow, use the blue/yellow method. If greens are a dominant part of many of your paintings, go with "tube greens". And what method do I use? Well, I first began watercolor with the blue and yellow method, but the more I painted, the more that I saw that greens were going to be a huge part of my pictures, so now I predominately use the "tube green" method.

 

The picture below shows the "tube green" "home base green" method I described above.

Notice how the "home base" of Sap Green in the foreground gives an overall harmony to the greens there, but they still are greatly varied. And note the "transition zone" where the cool greens change to warm greens. Using the Viridian and Sap Green "home bases" allowed this transition to take place almost seamlessly. This would have been much harder to accomplish with the yellow/blue method. And yes, there is pure Sap Green and Viridian in there, straight from the tube; lot's of it! But it looks fine, doesn't it?

 

The tutorial below shows the actual physical process that I go through to paint greens, detailing the "tweaking" that I mentioned above, and how I achieve tonal variations as well.

This tutorial was done back when I was using the blue/yellow method. but it could just as well be applied to using a pre-mixed green and tweaking it with other colors. The principles are the same.

Tutorial:

Preparation:  If you are doing more than the first step (base tone) and you want to work wet-in-wet, you should have all of your mixes (base, middle, and dark) prepared at the get-go.

Base tone: First, start with a base color/tone.  If are doing an area that needs relatively one tone, this is the only step you will need.  Here's what I do:
    I make a mix of whatever yellow and blue I need to get the color and brightness that I want.  I make sure it is a variegated (not one homogenous color) mix.
      As I begin to paint, I constantly tweak the mix by adding the two initial colors: yellow, blue, yellow, blue, yellow, blue... to keep the colors varied.  I change the amounts of each color about every two or three brush charges.
    The tricky part of this is that once you've begun, and you go to add yellow or blue to your mix to vary it, you are changing the consistency of the mix as well as the color.  So, if keeping the consistency is important (which it almost always is), you usually need to add water to the mix as you add the new paint. 
    Here's the bad news:  This is one of those times that being very confident with basic techniques is essential, and honestly, it is one of those things that just can't be done without a lot of practice.  Getting your mix consistency must be second nature, and you must be able to dip that brush into the paint, wipe the right amount onto the palette without changing the color too much, dip the brush into the water, perhaps dab it on a tissue, and then add just enough water to the mix to make the consistency right again.   And it all must be done FAST in order to keep your wash wet and juicy and to not have it drying on you.  The action must be just dob-wipe-dip-wipe in a matter of a couple of seconds.

Middle tone: If you need a deeper tone, say for defining shadows in a tree canopy, move on to this step:
    I make a separate mix of darker green usually made from Hooker's Green (any Phtalo based green will do) with touches of yellow or blue to approximate the greens used in the base tone. I use this mix to drop in at the "right moment" (a whole other topic) as the base tone wash is drying.  I keep this darker mixed varied too, and adjust it by adding one of the two colors about every two or three brush charges.

Darkest Tone: If you need deep darks, such as at the base of a heavy tree cluster, go on to this step:
    I darken my base mixture and/or my middle tone mixture even more with a black neutral tint and drop these in at the "right moment" for super darks My method for this is where I diverge from many painters.  Here's what I do:
    I always have made my own neutral tint instead of using Payne's Gray or other carbon based blacks.  I make this by mixing Hooker's Green (Phtalo) or some other very strong green with a strong compliment like Quin Rose, Dioxazine Violet, etc..  This gives a very dark, almost black green, and viola, your darks are adding even more variations of green.  And to boot, it doesn't dry so much lighter, like carbon blacks.  And, unlike carbon blacks, it is semi-transparent which allows some of the others greens underneath to show through.
    Recently, I have discovered that M. Graham's neutral tint is not made with carbon black, but with Phtalo green and Quin Violet (the same exact method I was using). I have never tried Phtalo Blue and Burnt Sienna for this, but I assume it would work well to, as it makes a very dark green (although it is usually a cool green so this might not blend with the other base and middle tone greens used earlier).  Winsor and Newton now offers a Perylene Green that is an almost black green right out of the tube.  I have used this, tweaking it a little to fit my base and middle tone greens, and it works brilliantly as well.

An update to this: I have now switched to Winsor and Newton's Perylene Green almost exclusively to darken my green tones. It is simply perfect for what I have described above.

Here is a sample painting with my tonal sections labeled: