The surprising answer is yes: botanically, peppers are definitively classified as berries. This classification highlights the significant difference between scientific taxonomy and how we use language in the kitchen. The structure of the pepper fruit, from its development on the plant to the arrangement of its seeds, adheres perfectly to the rules of plant science. To understand this botanical truth, one must examine the precise components that define a true berry.
What Defines a Botanical Berry
A true botanical berry, or bacca, is a type of simple fruit that originates from a single flower containing a single ovary. This results in an indehiscent fruit, meaning it does not split open to release its seeds when ripe. The defining feature of a berry is its entirely fleshy fruit wall, known as the pericarp, which surrounds the seeds.
The pericarp is composed of three distinct layers that ripen to a soft, pulpy consistency: the outer skin (exocarp or epicarp), the middle fleshy layer (mesocarp), and the innermost layer (endocarp). In a true berry, the seeds are typically embedded within the fleshy mesocarp and endocarp. Fruits like grapes and tomatoes exemplify this structure, forming an edible, fleshy mass around the seeds.
Applying the Definition to Peppers
The fruit of the pepper plant, belonging to the Capsicum genus, aligns precisely with the scientific definition of a berry. Each pepper develops from the single ovary of a single flower. This single-ovary origin is the fundamental requirement for classification as a simple fruit and a berry.
When examining the interior of a pepper, the entire fleshy wall we eat is the ripened pericarp. This wall is divided into the exocarp (the thin outer skin), the mesocarp (the main bulk of the flesh), and the endocarp (the thin membrane lining the seed cavity). The numerous seeds are housed within this internal cavity, suspended by the placenta, a fleshy tissue derived from the ovary wall. While many berries have seeds fully encased in pulp, the pepper is a modification where the seeds are often surrounded by air, but its underlying structure remains that of a berry.
Why We Call Them Vegetables
The classification of peppers as vegetables stems entirely from culinary tradition and cultural usage, not from botany. The term “vegetable” lacks a precise scientific definition and is instead a broad term used to describe edible plant parts that are savory rather than sweet. Peppers are overwhelmingly used in savory dishes, such as stir-fries, salsas, and main courses, separating them from sweet, dessert-type fruits.
This distinction by usage is the primary reason the average person considers a pepper a vegetable. The difference was legally cemented in 1893 when the U.S. Supreme Court ruled in Nix v. Hedden that tomatoes, which are also botanical berries, should be taxed as vegetables under tariff law. This ruling focused on how the produce was used—served with dinner rather than as dessert—and solidified the idea that culinary classifications could override scientific fact. Consequently, peppers and similar savory fruits are grouped with true vegetables like carrots and lettuce in grocery stores and dietary guidelines.
Other Unexpected Members of the Berry Family
The botanical definition of a berry is often surprising because it includes many items commonly mistaken for vegetables or other types of fruit. The true berry classification is shared by popular produce items that develop from a single ovary and have a fleshy pericarp.
Bananas are true berries, despite their elongated shape, because they develop from a single flower with a single ovary and have tiny, undeveloped seeds within their flesh. Tomatoes, closely related to peppers in the nightshade family, are another clear example, featuring a fleshy wall and multiple seeds. Eggplants also fit this description, as do grapes, which are the quintessential example of a simple berry.