Step 3
Using the pen tool and looking at the reference, start drawing the objects. Try sticking to two-to-three colours per object – this will make getting the right overall colour scheme easier. With symmetrical objects such as a tomato you can draw one side first, duplicate it and place it on the other side. Select the in-between points with the direct selection tool and Option/Ctrl-click-Join to join them.

Step 4
Continue to draw more objects. You may want to compare them to each other to make sure they are a similar style, both in shape and colour. You could use one of illustrators swatch libraries such as Window>Swatch Libraries>Fruits and vegetables to keep the overall colour consistent.

Step 5
Once you’ve drawn plenty of objects, try drawing some vernacular shapes. These will help you fill in the spaces in between your objects and can also be a good way to add colours. Try using the grid to keep the curves and proportions the same as the rest of your objects.

Step 6
Now that you have all the elements you need, you can start to make the pattern. I like to start by making a shape that tiles by itself to use as a guide. Try drawing a square and draw a shape that reaches from the bottom-right corner to the top-left corner. Now use this shape to form four sides of a new shape making sure the bottom-left shape is facing the same way as the top right and the same goes for the bottom right and top left. This will make sure they tile.