There are a lot of different ways to color grass, and I have done a variety of grass coloring tutorials in the past, but this one I absolutely love because it can quickly create a very detailed effect of a grass field without having to spend a long time defining the blades.
This series has become focused on using the sky in the rest of the scene to help create a more blended, cohesive look to the coloring page. Over the next few days, we will be visiting a lot of different greenery scenes and the sky.
It is my goal overall with this series to help inspire new techniques to try.
Grass Coloring Tutorial
Now, my favorite part of this whole tutorial was watching the first charcoal hit the page to define the texture of the grass, as well as put down some blades of grass. I highly recommend playing around with different directions for the blades and adding some details like leaves, as grass fields are made up of a variety of plants. 
Tools Used
I am using Honolulu B Alcohol Markers in new and old codes, Pandafly charcoals, and Kalour colored pencils, along with an Arrtx acrylic for this look.
Grass Coloring Tutorial Video
This tutorial in real life took me 10 minutes to do, and as always, it is sped up to under a minute for you!
Grass Coloring Tutorial Step-by-Step
Step 1: Use BV31 to color in the sky
Step 2: At the horizon, color in flick motions some blades of grass with BV31 for depth and shadow.
Step 3: Color in shadow patches for the grass with BV31.
Step 4: Use MG060 to add some blades along the horizon.
Step 5: Go back over it with more BV31 to blend and darken the horizon line.
Step 6: Use a green charcoal to define some grass texture in the field and smudge it.
Step 7: Still using the green charcoal, create patches of green grass blades.
Step 8: Use a purple charcoal to define more grass blades that provide depth.
Step 9: Use a blue charcoal to define some more grass blades, especially on the horizon, and then back over some of the grass field to darken some shadows.
Step 10: Next, use a grass green colored pencil that is lighter than the green charcoal to define highlighted blades of grass. This is also a good spot to sneak in some different types of plants with leaves, etc.
Step 11: Use purple and white acrylics to create some wild flowers.
Step 12: Purple charcoal over the purple flowers and use BV31 over the white to give some details on the flowers.
Step 13: And finally, use MG060 to bring in any depth and shadows for the grass blades.
This tutorial is a little longer, but it is just about layering through the steps and adjusting to preference as you go. This is absolutely a grass coloring tutorial you could get more detailed with, by using acrylic pens/gel pens, or even more colored pencils.
The next few days will continue the discussion of using the sky with the landscape!