phyllotaxis

leaf arrangement

Written by

The Information Architects of Encyclopaedia Britannica

Last updated

July 1, 2026

Quick Summary

Phyllotaxis refers to the arrangement of leaves on a plant's stem. This arrangement follows specific patterns, which are studied to understand the underlying laws governing them. The three primary patterns of leaf arrangement in angiosperms are alternate, opposite, and whorled. In alternate arrangements, leaves appear singly at each node and spiral up the stem. Opposite arrangements feature paired leaves at each node, directly across from each other. Whorled arrangements occur when three or more leaves are equally spaced at a single node. The term "phyllotactic" is an adjective used to describe something related to phyllotaxis.123

Summary created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

4 Britannica Sources

Ask Britannica AI about this topic

Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.

number game
Fibonacci numbers
…the botanical phenomenon known as phyllotaxis. Thus, the arrangement of the whorls on a pinecone or pineapple, of petals on a sunflower, and of branches from some stems follows a sequence of Fibonacci numbers or the series of fractions
Read More
…the botanical phenomenon known as phyllotaxis. Thus, the arrangement of the whorls on a pinecone or pineapple, of petals on a sunflower, and of branches from some stems follows a sequence of Fibonacci numbers or the series of fractions
Read More

angiosperm
Leaves
The three patterns of leaf arrangement on stems in angiosperms are alternate, opposite (paired), and whorled. In alternate-leaved plants, the leaves are single at each node and borne along the stem alternately in an ascending spiral. In opposite-leaved plants, the leaves are paired at a node and…
Read More
The three patterns of leaf arrangement on stems in angiosperms are alternate, opposite (paired), and whorled. In alternate-leaved plants, the leaves are single at each node and borne along the stem alternately in an ascending spiral. In opposite-leaved plants, the leaves are paired at a node and…
Read More