Above is two petunia blooms growing on the same petunia plant and from the exact same stem.

One is the familiar speckled purple of the "Night Sky" cultivar https://pbase.com/britestar/image/173907604
The other is a solid burgundy flower that resembles the cultivar "Starry Skies Burgundy" without the white markings https://pbase.com/britestar/image/174952671

What is happening to the burgundy flowers on my 2025 "Night Sky" petunia is a spontaneous change within the plant itself.

In plant biology, this kind of shift is called a sport—a mutation that happens in a single cell and spreads through part of the plant. It can change how the flower produces and arranges its pigments, which are the compounds that give petals their color. In this case, the mutation likely affected how anthocyanins (the pigments responsible for red, purple, and blue tones) are expressed.

Both "Night Sky" and "Starry Skies Burgundy" petunias were bred by Selecta One and belong to the same series. They both share a genetic background that includes older petunia species known for deep purple blooms. The "Night Sky" petunia above (both flowers) is probably tapping into a shared ancestral trait with its cousin "Starry Skies Burgundy". Something buried in the plant’s genetic history has surfaced with the burgundy flowers.

This kind of mutation is rare but not unheard of, especially in hybrids. It’s a quiet reminder that even stable cultivars can surprise us, and that plants carry more history than we often realize.

Night Sky was officially launched by Selecta One in 2016, during the California Spring Trials, where it was celebrated as a breakthrough in petunia breeding. It was the first in what became the “Sky” series—cultivars with temperature-sensitive speckled patterns that mimic constellations. Starry Skies Burgundy (also marketed as Headliner™ Starry Sky Burgundy) followed later.

When a cultivar series is relatively young—like the Sky series from Selecta One, it hasn’t had decades of generational selection to fully suppress ancestral traits. That means the genetic architecture is still somewhat “loose,” especially in hybrids bred for dramatic patterning. Their genetic complexity makes them more prone to spontaneous shifts—whether through somatic mutation or re-expression of dormant traits.

When a "Night Sky" petunia throws a burgundy sport like above, it’s not just a curiosity—it’s a glimpse into the cultivar’s genetic memory.
Just another day on my deck...