Hi there Ricardo, congratulations on your great layout, you must have spent a lot of money on it, I like the "green scenes" since they are my favourites, I use the same grass as you do but to get the effect I want I usually deploy three layers of it. The last one doesn't get anything on top (to fixate), this gives the grass a more natural look.
You can see my very small layout in this thread:
http://www.the-gauge.com/forums/showthread.php?s=&threadid=7389
Just a few questions since is the first time I see your posts around here:
In what scale is the layout?
What's the size of the layout?
Do you buy the modelling products online or in places like Dentinho or Gotita...?
Unfortunately in Portugal modelling products are very expensive, at least for our living standards
Keep up the good work, oh and if possible an overview picture would be great.