Glow-in-the-Dark Firefly Petunias

This year we had the chance as professional growers to try out the new Firefly petunias.

We had first heard about these petunias in 2024, but we weren't ready to jump on board with a novelty item as our greenhouse space is very limited. Fast forward to late winter of 2025, we decided that we should try out the Firefly petunias after our wholesale plant rep encouraged us that even though they were pricey, the few greenhouses that had them had crowds turning out to buy them.

We decided to plant up the Firefly petunias in 6" pots instead of 4" containers so that they would have the best chance for growth. At first they took their time and grew very slowly, which was expected from talking to our plant rep. They were a low to medium vigor petunia. We fed at least twice a week with our Beat Your Neighbor fertilizer, and suddenly at around week 3 they really took off!

We kept checking to see the glow, bringing the plants inside into an interior room with no windows, but there just wasn't much glow yet. We decided not to announce that we had the Firefly petunias until we could see that they truly do perform.

Once the Fireflys started to fill out the 6" pots is when the glowing started to happen. We went out into our greenhouses toward sunset and were surprised that suddenly they were really lighting up. We were so excited to see that these actually do what was promised, but it takes some time and growth before they really glow.

So, once you see for yourselves these very unique petunias are actually quite impressive. Give them some time to grow and fill out before expecting a brilliant glow. You do need to be in a dark area, so make sure outside lights are off and there isn't any light source filtering in. It's amazing once you notice how much of the plant is glowing. The brightest are new blooms, as they seem to be concentrated with the bioluminescence. But leaves, stems and supposedly even the roots will glow too.

Check out the new Firefly petunias in our video below: