Do Stems Grow Up? Geotropism is the influence of gravity on plant growth or movement. Simply put, this means that roots grow down and stems grow up. Upward growth of plant parts, against gravity, is called negative geotropism, and downward growth of roots is called positive geotropism. … Do all stems hold plants upright? What
What Are Horizontal Underground Stems Called? Rhizome, also called creeping rootstalk, horizontal underground plant stem capable of producing the shoot and root systems of a new plant. Rhizomes are used to store starches and proteins and enable plants to perennate (survive an annual unfavourable season) underground. Which group of plants has a horizontal underground stem?