Rose, it looks very good! I love your compositional change--and that little lamb looks very fluffy all snuggled next to mama. The contrast of the textures is working quite well.
To darken the green you might try layering
instead of blending. Where you need it darker use the big, flat side of the pastel to lay down some strokes of dark blue, purple or even black (or all of these!) and cover with strokes of your darkest green. Where the grass is lighter use yellow, peach or gold under the light green. You can then use the point or sharp edge of the pastel to stroke in the blades of grass with your two greens. You could apply this idea to any of the textures--the wooly lamb and the ragged mama sheep.
What kind of paper are you using? With pastels it really pays off to have more tooth, which is why I like sandpaper so much. Wallis is my favorite but there are others that are good, too. The pads they call pastel or charcoal paper really challenge beginners, because there is more nap than tooth. I always have my beginning students work on sandpaper--and, yes, you can try plain old furniture grade 600 grit wet and dry sandpaper, but it's not archival in any sense! PM Kitty Wallis and get a sample of her paper, if you haven't already.
I wasn't jumping on you about March, Rose!
My brain is fuzzy with a cold and I thought you were asking where the older threads were located... I'll get to March before the month wanes if I get over the cold/allergies soon enough to make some demo paintings! If not, we'll make it April. Keep your eyes open.
Thanks for taking part. Anyone else have anything to share??? Now's the time...