Mine germinated in the garden, self-sown just yesterday, here in zone 7 NC! They are easy to recognize. The white outer seed coat is still intact the first couple days after gemination, clinging to the tip of the seedling. The seedling leaves are large and wrinkled-looking like a brain, before they shed the seed coat and open up. When open, each seedling leaf is large, about a square inch, and shaped like a butterfly. They are unusual enough to stand out.

You could grow your own from seed then take a pic with your digital camera and save it on your computer.