There is an easy way to generate Vector grass in Illustrator. Start by creating a single grass blade and we can generate an entire grass pattern in minutes.

Let’s get started:

STEP ONE:

Create a New Illustrator Document, File > New. Name it: “Realistic Grass”, and give it a size of 400px by 200px.
Open the LAYERS palette (Window > Layers (F7)) and rename “Layer 1” as, “grass blade”.

STEP TWO:

Select the Pen Tool (P) and draw a shape similar to a grass blade.
Here is how my shape looks like:
Step Two

STEP THREE:

Select the Rectangle Tool (M) and create a rectangle that covers the entire grass blade shape.
Step Three A
Fill the rectangle with a green color, I used (C= 84%, M= 0%, Y= 100%, K= 22%), no stroke.
Now, send the rectangle to the back by selecting it and going to Object > Arrange > Send to Back.
Then, fill the grass blade shape with white, no stroke.
Step Three B

STEP FOUR:

Select the green rectangle, go to Object > Create Gradient Mesh, and enter the following settings:
Step Four

STEP FIVE:

Select both shapes and go to Object > Clipping Mask > Make.
Now, select the Direct Selection Tool (A) and move the points of the rectangle closer to the grass blade shape.
Step Five

STEP SIX:

Select the Mesh Tool (U) and add some vertical lines, like shown below:
Step Six A
Now, with the Direct Selection Tool (A) select the new paths and add a different shades of green to them:
Step Six B

STEP SEVEN:

Let’s create the veins of our grass blade. Select the Pen Tool (P); with a dark green (C= 90%, M= 30%, Y= 95%, K= 30%) 0.25 point stroke draw two paths around the border of our shape.
Step Seven A
Now, select the two paths and double-click the Blend Tool (W). Enter the following settings:
Step Seven B
Click OK, with the two paths selected go to Object > Blend > Make.
Step Seven C
With the two paths still selected go to Object > Blend > Expand. When we expand a shape each path became editable. With the Direct Selection Tool (A) we can select each line and edit them by changing their stroke width and color. In this case we are going to fill the paths with a gradient.
Select the lines, go to Window > Gradient, and apply the following gradient:
Step Seven D

STEP EIGHT:

Select All (Control + A) and go to Object > Group.
Now that we have our grass blade ready, open the SYMBOLS palette, (Window > Symbols), and drag our entire grass blade shape inside the SYMBOLS palette. When you drag the shape the Symbol Options dialog box will appear, enter the following settings:
Step Eight A
Notice that now our shape is inside the SYMBOLS palette:
Step Eight B

STEP NINE:

Double-click the Symbol Sprayer Tool (Shift + S) and enter the following settings:
Step Nine
Start spraying around your grass blade to create a nice grass field. Remember that you can tweak its size, color, or opacity just by double-clicking the Symbol Sprayer Tool (Shift + S).

This is my final result:
Final Result

Now that we know how to create a grass blade, we can create two more different grass blades, save them as symbols, and play around with the symbol Sprayer Tool to create a more realistic grass effect.

Download Source Files