Effecient grass for mobile devices

I want to cover a small surface with tall grass. I’ve tried Unity Terrain (for the first time), covered my whole area with grass, but I get a couple of thousand draw calls, which renders the game unplayable to any mobile device.

The game I’m working on has an Augmented Reality environment, so I need the whole area of grass to be visible at all times (thus it makes no sense to reduce the “detail distance”, in fact, I have to raise it all the way to the top).

I thought of editing the grass.psd file and tile the whole thing a few times horizontally so that I would have to paint less pieces of grass, but I’m having some trouble with that, don’t even know if it would look good enough.

Is there anything else I can do?

Try lowering your detail resolution and raising your detail resolution per patch. I was having a similar problem and once I raised my resolution per patch from 8 to 32 I saw a huge drop in draw calls and only a small difference in grass density. Turning grass billboard off will help it to appear denser as well.