Curiosity | Plant Anatomy

The Tiny Fruits on a Strawberry’s Surface

Small dry fruits cover a fleshy flower base. A strawberry’s anatomy makes sense when you follow how its flower develops.

Close-up of a red strawberry with pale achenes set into dimples on its surface.
Strawberry surface, June 20, 2022. The pale structures are achenes. Photo: IceuImgflip / Wikimedia Commons, CC BY-SA 4.0. Uncropped Commons resized version. The photograph remains under that license.

A seed inside a tiny fruit

The pale dots in a strawberry’s dimples are called achenes. Each is a small botanical fruit of the one-seeded type, with a seed enclosed by a dry fruit wall. That outer wall is part of what you see on the surface.

The University of Sydney’s botanical glossary defines an achene as a dry fruit that stays closed at maturity. Its seed is separate from the surrounding fruit wall. “Dry” describes this little fruit, even though the much larger structure carrying it is juicy.

One flower, many ovaries

A strawberry flower has numerous separate carpels, the reproductive structures that contain the ovaries. They sit together on a common receptacle: the flower’s supporting base. Within the ovaries, fertilized ovules develop into seeds.

The University of Illinois’ flower-to-fruit account follows the two developments side by side. Each carpel matures into an achene, while the shared receptacle enlarges and becomes fleshy. This explains the arrangement: many small fruits remain on the outside of the expanded flower base.

White garden-strawberry flowers and small developing green strawberries among leaves.
Garden strawberry flowers and developing fruit, April 29, 2012. The source identifies Fragaria × ananassa. “Flower of Fragaria × ananassa.JPG” Photo: Alpsdake / Wikimedia Commons, CC BY-SA 3.0. Uncropped Commons resized version. The photograph remains under that license.

What “aggregate accessory fruit” means

Botanists use two complementary labels for the whole strawberry. The University of Minnesota’s horticulture textbook explains them through the tissues involved:

  • Aggregate: numerous ovaries from a single flower contribute separate small fruits.
  • Accessory: tissue beyond the ovary contributes to the structure. In a strawberry, that is primarily the enlarged receptacle.

The terms describe different aspects of the same development. Aggregate tells you how the small fruits are grouped; accessory identifies the origin of much of the flesh. The familiar strawberry can therefore be described as an aggregate accessory fruit without treating its everyday name as an error.

Cut strawberry pieces showing red flesh, pale centers and achenes along their outer edges.
Cut strawberries, December 13, 2025, according to the source’s camera metadata. The broad fleshy interior is visible. Photo: Dprzvhar / Wikimedia Commons, CC0 1.0. Uncropped Commons resized version.

Reading the cut surface

The cut strawberries pictured above show a broad fleshy interior, while the opening photograph shows the separate surface achenes. Together, the views help distinguish the enlarged receptacle from the tiny fruits it carries. The seed enclosed inside an achene is smaller still; these ordinary close-ups do not expose that internal seed.

Sources and photograph notes

Checked October 15, 2026. This source-based botanical explanation includes three illustrative photographs; it does not describe an OnelROR experiment.