Home	Cotyledons or seed leaves

In small seedlings, we talk about dicotyledons (which have two cotyledons or seed leaves) and monocotyledons (which have just one seed leaf). The seed leaf is the very first leaf to grow on the baby plant, and it looks quite different to the final shape and size of the adult leaves. That is one reason why it is so hard to tell the difference between plants and weeds when they are very tiny - they all look alike!

On the bean plant to the right, you can see the two oval cotyledons, which are quite a different shape from the final bean leaves on the older plants at the back. As the plant gets older, the leaves take on the mature form, and it is easier to see what kind of plant the seedling is growing into.