The easiest way to blend colors in Inkscape is by using color gradients. Here is an exercise to create a simple ground cover or part of a forest floor.
- Create an irregular shape like this using the Pen Tool or other drawing tools. Fill the shape with a shade of green. Remove the stroke color. If you wish to keep the stroke color, match it with the fill color.

- The shape can also be created using the Circle, Ellipses and Arcs tool. Draw an ellipse using this tool and flatten it using the selector tool.