What is it?

For Christmas 2020, I drew my sister-in-law, Alexis, in the family gift exchange. I had no idea what unique gift I could giver her… but I knew I would probably have to make something. Challenge accepted!

Monica gave me some useful tidbits… “She likes flowers”, and I already knew she liked things with some science aspect. I would spend the next few days coming up (and discarding) various ideas until I was cutting the grass and it dawned on me, name and all:

The Night Blossom is a unique, hand-made flower that only blooms at night. Its glow comes from 15 separate vials of gaseous, radioactive tritium. Tritium emits electrons through beta decay and is the only radioluminescent light source still in use.

Tritium beta radiation is safe, as it is insufficient to penetrate human skin. The half-life of tritium is about 15 years

This is not your typical “glow in the dark” item. Because of the radioluminescence, the flower is glowing constantly. Even during the day when it’s too light to notice. At night, it produces a soft glow that is just enough to be pretty, but not enough to be distracting. I imagine some alien planet where fields of Night Blossoms flourish…


That golden flower in the middle was my original (overly simply) concept

It started with a relatively simple idea, but things quickly got more involved. After several test iterations and 3D test prints, I arrived at an original design for the petals, bud, and stem.  The prints were sanded, and a custom-tinted epoxy was applied to get the proper effect. The epoxy adds an almost “blown-glass” quality.

The vials were inserted into the petals and bud, which were then glued in place. The stem was finished in a similar manner and glued to the back to permanently encase the tritium.


I wasn’t sure how to present the item, but I knew I wanted an “Apple-esque” experience when Alexis opened it. I also knew she was going to have to travel (by plane) with it, so it had to be protected somehow. I searched several stores and online for the perfect box and came up empty, so I wound up making that, too.

This turned out to be a good solution, because when the family decided to cancel travel due to the pandemic, I had to ship the present to California. I added a little extra foam to the box and it survived the trip.

Tritium vials used in construction:
Quant 5, T1 1.5x6mm Vials (yellow)
Quant 5, T35 3.5x25mm Vials (yellow)
Quant 5, T315 3x15mm Vials (white)

The stem is “unlit” in Alexis’s version, but Monica has requested a glowing stem for hers.

It seems to be getting harder to find tritium vials in the correct sizes. I am not sure if this is pandemic related or something else. I knew the project was going to be a success when Monica asked me to make her one for Valentine’s Day. But for now, I can’t find the materials I need online. Alexis’s flower may truly be unique.


Text from Alexis on Christmas morning: “Coolest. Present. Ever.”

Mission Accomplished!

2021 Update:

I finished Monica’s Night Blossom for Christmas this year. Tritium vials have been hard to come by, so I had to make some substitutions. For this version, I used the following types:

Quant 5 T1 1.5x6mm Vials (yellow)
Quant 5 T2b 2x12mm Vials (white)
Quant 5 T3a 3x25mm Vials (yellow)

Basically, the “bud” vials are the same (T1) but the Yellow petals are slightly thinner (3mm vs 3.5mm) and white vials are slightly shorter (12mm vs 15mm) and thinner (2mm vs 3mm). But that’s what I could get! I mostly constructed this NB the same way, but I did use my new SLA printer instead of my FDM printer. The large yellow petals were coated with tinted epoxy, but for the bud and white petals I added tint directly to the SLA resin.

SLA printers can print much clearer than FDM printers. The clearer printing has advantages and drawbacks: I don’t think the petals diffuse the light as much, but I also think it’s a little brighter because of that. And the bud is not only more clear, but now it has a neat “ring” effect that is lacking in Alexis’s version. Overall, it’s similar but still unique in its own way.