Optimizing vegetation.

Hi, I'm currently working on a scene that has a lot of grass in it - I used the terrain tool in Unity, and painted the grass on to it, nothing fancy. However, it raised my draw calls to more than twice the amount it was before.

Looking at the island demo from Unity, they have roughly the same amount of different plants as me, but their vegetation is actually much more dense, and with roughly the same detail settings. And yet, their vegetation amounts to 300 draw calls or so, while mine hits close to 1000...

I've scoured the internet trying to find out the reason, but I have not been able to find a single article or thread that deals with this problem. Am I missing something essential here?

As far as I can tell, my settings for both the terrain and the vegetation are low to moderate. Because of a technical issue, I have more than one terrain in the scene and someone suggested that might be the cause, but removing the second terrain didn't improve the situation at all.

Any help?