How Stems Support Plants

A stem is the part of a plant that connects the roots underground to the leaves above ground. Stems are important because they hold the plant upright and position the leaves where they can catch sunlight. Without stems, plants could not stand tall or spread their leaves to make food through photosynthesis.

Stems come in many different forms depending on the type of plant. A daisy has a thin, flexible stem that can bend in the wind without breaking. Flexible means able to bend easily. A tree has a thick, woody stem called a trunk that provides strong support so the tree can grow very tall. Woody means hard and rigid like wood. Some plants like ivy have climbing stems called vines that wrap around objects for support. Think of a stem like a straw in a drink box—it connects the liquid at the bottom to your mouth at the top.

The external structure of the stem—its thickness, strength, and flexibility—determines how tall a plant can grow and how it holds its shape. External structure means the outside form and features of something. Thick, woody stems allow trees to reach heights of over 100 feet, while thin stems keep smaller plants closer to the ground. Stems also create a pathway that moves water from the roots up to the leaves and carries food made in the leaves down to the rest of the plant.

Interesting Fact: The tallest tree in the world is a coast redwood named Hyperion that stands 380 feet tall—that's taller than the Statue of Liberty!