Let’s discuss the anatomy of a seedling! We find it helpful to know what it is we are looking at as it gives us a way of both understanding and describing the plant’s growth.
The “classic” seedling that most are familiar with produce two seed leaves in their initial growth. The “proper” name used for this initial growth is the cotyledon. These two leaf seeds are called dicots because there’s two initial leaves. You can also describe this plant as dicotyledonous.
You may also be familiar with plants that produce a singular initial leaf or stem, such as an onion or grass. The initial growth is also called a cotyledon, but a single leaf is called a monocot for the single leaf or stem. These are called monocotyledonous plants.
These initial leaves produced from a seed are called embryonic leaves. The reason for this is because the seed itself provides all the necessary energy needed to produce them. They establish the ability for the seedling to photosynthesize, essential for further growth.
When you see further growth from the plant, the first leaves you see after the cotyledon are what we call first true leaves. This is also true in monocots, but some call this growth a stem or the main stem. These are post embryonic leaves, since the energy used to create them are created by the seedling itself.
One of the important things to know, when it comes to plant health and diagnostics, is you should generally ignore the cotyledon. Many plants will shed these leaves once true leaves develop, they are inconsequential to the plant.
There are a few other examples, but they’re much more rarely seen. Some pine trees can produce as many as two dozen cotyledons, these are called multicotyledonous. Many species of orchids don’t produce a cotyledon, these are called acotyledons.
So, that’s the basic language of the seedling! And yes, you plant nerds, we know we left some stuff out. Our posts are necessarily concise!
