In the video below, you'll get to see one such trick in the making. Using a wax-like substance, this man is creating fake cabbage to be used in a food display and photography. Real cabbage would wilt and oxidize after only a short while, but this stuff will last forever.
It all starts with a ladle of green and white wax.
It's then manipulated into a leaf-like texture.
Here, it kind of looks like Jabba the Hutt, but that probably wasn't intentional.
Watch the weird, wonderful magic here:
The next time you see a bright, fresh-looking vegetable in an advertisement, remember this video. It's probably wax!