What on Earth Is It Called “Dog’s Balls”!? The Tiny Blue Flower Veronica persica and Its Shocking Survival Strategy [Viewer Discretion Advised!?]

I’m Ken Kuwako, your Science Trainer. Every day is an experiment!

【This article is also available on Radio!】

Tiny blue flowers scattered at your feet, looking just like a handful of sapphires. Have you ever noticed these charming little blossoms while taking a spring stroll? Today, I’d like to introduce you to the Persian Speedwell (Ooinunofuguri), the very first messenger of spring. While it’s often dismissed as just another common weed, this tiny plant actually packs some incredible “high-tech strategies” to survive the harsh realities of nature.

The Name Gap and Heart-Shaped Fruits
First, let’s talk about its name, which has a bit of a shocking origin—one you’d never guess from its delicate appearance.

In Japanese, the name Ooinunofuguri translates literally to… “Great Dog’s Scrotum.” Yes, you read that right! It was named by Dr. Tomitaro Makino, the “Father of Japanese Botany” (and the inspiration for a popular Japanese TV drama).

牧野富太郎先生のスケッチにびっくり！高知県立牧野植物園

He named it after a native Japanese species called Inunofuguri because their fruit shapes are similar, but this one has larger flowers.

Image via Kujo-yama Kyoto Nature Observation Diary: https://net1010.net/2008/03/id_1630/

If you look at the photo, you can certainly see two plump, heart-shaped fruits sitting side-by-side. On a more romantic note, its beautiful blue color has earned it the nickname “Star’s Eyes.” This huge gap between its names is part of its charm! By the way, this plant is actually an introduced species in Japan.

Winter Survival: Natural Insulation
The Persian Speedwell is a “winter annual,” meaning it grows close to the ground during the winter while other plants are withered away. It stays perfectly unfazed by the freezing cold thanks to two clever secrets.

The first is its “Natural Antifreeze.” By intentionally increasing the concentration of sugar within its cells, the plant prevents itself from freezing even when temperatures drop below zero. It’s the same principle as why thick sugar water is harder to freeze in a science experiment.

The second is the “Down Jacket Effect.” If you look closely at the stems and leaves, they are covered in tiny hairs. These create a layer of trapped air, acting as insulation that prevents frost and snow from making direct contact with the plant’s surface.

A Two-Step Pollination Strategy: Failure is Not an Option
For flowers blooming in early spring, the biggest challenge is the lack of insects. No matter how pretty the flower is, it can’t produce seeds if there are no bees or butterflies to carry the pollen. To solve this, the Persian Speedwell has a perfect backup plan.

First, it uses nectar in its center to lure insects, aiming for cross-pollination (breeding with other flowers). However, if no insects show up, the two stamens curl inward as the flower wilts, touching their own pistil.

This is called “Automatic Self-Pollination.” Its risk management is top-tier: “Ideally, I’d like some genetic diversity through cross-pollination, but at the very least, I’m making seeds by myself!” As a result, a single plant can produce an amazing average of 545 seeds. (Reference: Wikipedia)

The “Contrarian Strategy”: Winning by Starting Early
Why do they bother blooming while it’s still so cold? It’s all about “Avoiding Competition.”

Once summer hits and tall grasses take over, the sun can no longer reach the Persian Speedwell, which lives low to the ground. That’s why it grows rapidly in early spring when its rivals are still asleep, allowing it to monopolize the sunlight.

Its “One-Day Flower” cycle—opening in the morning sun and dropping off by evening—is another piece of wisdom to avoid wasting limited energy. The next time you spot these blue flowers by the roadside, try kneeling down for a closer look. You’ll find a story of resilient life, hiding a universe of strategies within a tiny body.

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