The question that you are asking is a very common one, but the answers are not as straight forward as you may think. How does a professional make the colors so bright, the contrast so well defined, the focus so perfect, etc ? Well, it isn't just one thing, ever. It isn't a single setting on the camera, or a single post processing technique or button. It is a combination of talent, skill, technique, equipment, patience, etc - all things that cannot be adequately described in a short answer such as this.
The article "Magic Camera Settings" by Thom Hogan really gives a great example of this. Many times amateur photographers are looking for one magic bullet, such as a setting or preset - but you will find none that gives such a general "pop" to photos, as it is a combination of many things.
I won't leave you without helping you out a bit though :) I would suggest picking up a circular polarizing filter. It will help a great deal in giving your greens a very rich vibrant green color. It also helps blues to pop, and can assist when reflections exist in the frame as well. As for post processing, you can use sliders in Lightroom for vibrance, saturation, and clarity to get the photos to pop. You also can single out the green channel and boost the saturation of just that. Don't go too overboard though or you will end up with a very fake looking photo.