How to Plant, Grow, and Care For Firefly Petunias
Conventional petunia by day, glowing blooms by night. Engineered with bioluminescence from mushrooms, Firefly petunias set the garden aglow. Explore this pioneering petunia with gardening expert Katherine Rowe.
While ‘Firefly’ petunias are always glowing, we don’t experience their hidden power until....

the sun goes down. The magical, mysterious, glow-in-the-dark creation stems from years of research surrounding bioluminescence.
Genetically modified for a modern twist on an old garden favorite, ‘Firefly’ petunias bring new light to summer evenings spent outdoors. Sure to spark interest in budding scientists and young gardeners, this very different petunia masquerades as common by day and otherworldly by twilight. Explore the how’s and why’s behind this petunia’s glow-up as we marvel at the notion.
What are ‘Firefly’ Petunias?
Genetically engineered to produce light through bioluminesence, ‘Firefly’ petunias emanate a soft, moonlit glow when the sun goes down or in a dark room. Its bright white blooms and buds produce the most light with a continual reaction harnessed by the sun’s energy.
The glowing qualities are a result of mushroom DNA. The annuals have four genes from a bioluminescent mushroom (Neonothopanus nambi) and a fifth from another fungi. The different genes play roles in a chemical reaction that produces organic light in leaves and flowers.
‘Firefly’ was ten years in the making with a team of scientists in coordination with the company Light Bio of Ketchum, Idaho. The USDA-approved specimen went on the market in late winter of 2024. It’s currently available only in the U.S.
‘Firefly’ plants grow like other petunias and don’t require special treatment or care. They’ll grow in beds, hanging baskets, and containers. Petunias bloom all summer until fall’s cool temperatures for an extended “glowing” season.
Characteristics
Identical to conventional petunias, except with bioluminescence, these have the same appearance as the favorite garden performer. Crisp white blooms top leafy stems that mound and reach eight to ten inches tall and wide.
Best viewed at twilight, the petals illuminate a greenish-white moonlight glow. New leafy growth, buds, and blooms are the brightest. The creator likens it to fireflies alighting on the plants. Eminence fades as the flowers age. Maintaining healthy growth through proper cultural requirements yields the most vigor and the best illumination.
While horticulturists hybridize selections every day to improve plant characteristics and landscape performance (including many petunias), this one differs in its cross-species DNA modification. More research is necessary to determine how the natural environment, particularly insects, wildlife, and surrounding plants, responds to the light.
Reportedly, creators chose the petunia because of its ornamental value, popularity, and diminished likelihood of genes spreading to other plants or the natural environment, as garden petunias aren’t invasive like other species may be. The intention is to market these unique ornamentals for the home garden or as houseplants rather than having widespread agricultural applications.
The pioneering petunia opens the potential for future bioluminescent discovery for soothing, non-artificial light sources. What becomes of this is up to the consumer; for now, we have a glowing bloomer to consider.
Native Area
Petunias originate in South America. What we commonly grow are from a large family of hybrids. Of garden origin, the annuals begin growing in cool springs and flourish in warm conditions of a mild summer. While tolerant of heat, they thrive in more moderate conditions.
Planting
Plant ‘Firefly’ where you’ll enjoy its illumination up close, in seating areas, at entrances, or as viewpoints. Petunias perform beautifully in containers, window boxes, and hanging baskets for added color and texture.
Provide ample air circulation between plants to prevent fungal issues. Allow spacing of about one foot.
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