This little project turns one plain mason jar and a can of expanding foam into a spooky lantern that looks like a weathered old tree stump after dark. The magic is in leaving small glass openings in the jar, so when the LED candle glows inside, the light peeks through like windows, cracks, and knotholes in bark.
I love projects like this because they lean heavily on texture and paint, not precision. If you can pipe frosting onto a cake or build up a good chili in layers, you can make this lantern; the trick is simply to let the foam stay lumpy and organic so the finished stump has that gnarled, believable look.
Materials
Instructions
1. Cover your work surface with the plastic tarp, put on disposable gloves, and make sure the mason jar is completely clean and dry so the foam can grip properly.
2. Cut 2 or 3 paper shapes for the light openings, then tape them onto the outside of the jar where you want your glowing “windows,” crack, or knothole to show later.
3. Shake the expanding foam can well and begin squirting foam around the lower half of the jar in thick, uneven mounds, leaving the top opening of the jar clear so you can still insert the candle.
4. Continue building the foam upward around the sides in lumpy passes, stopping below the jar rim and varying the thickness so it looks rough and knotted instead of smoothly coated.
5. Add extra blobs and ridges around the taped paper shapes to make those areas look like natural bark growth around an opening, then set the jar aside on the tarp to cure overnight.
6. Once the foam is fully cured, peel off the taped paper shapes to reveal the bare glass openings, then use the serrated bread knife to carefully trim the foam into a tree stump silhouette with slightly tapered sides and a rugged top edge.
7. Slice shallow vertical grooves, notches, and bark lines all around the foam so the surface reads as wood grain rather than puffy foam.
8. Paint the entire foam surface with brown acrylic paint, working it into every groove, and leave the glass openings and the inside of the jar unpainted.
9. Dry-brush black paint into the deepest creases and around the window, crack, and knothole edges to add age and shadow, using very little paint on the brush at a time.
10. Dry-brush white paint lightly over the raised bark texture and top ridges to highlight the stump and give it that weathered, haunted look.
11. Tuck small wisps of Spanish moss into a few crevices near the base and upper bark ridges while the paint is still slightly tacky, or press it into tiny leftover pockets in the foam.
12. Place the battery LED flicker candle inside the jar, turn it on, and adjust the lantern so the glowing openings face forward where the light shows through best.
Variations & Tips
Make the glow stronger: Keep your paper shapes fairly open and avoid burying them under too much foam. I like one larger knothole plus one thin crack so you get both a bright glow and some fine detail.
Shape it like real bark: Don’t over-trim. Tree bark looks best when some areas stay chunky and irregular, and that slightly wild texture is what makes expanding foam such a good material here.
Paint in layers: If the brown coat looks flat at first, that is completely normal. The bark effect really comes alive only after the black shadowing and white dry-brushed highlights go on.
Use moss sparingly: A little Spanish moss adds age and drama, but too much can hide the bark texture and the glowing openings. Tuck in small wisps rather than wrapping the whole stump.
Try different opening shapes: A rounded knothole feels woodsy, a jagged crack looks eerier, and a tiny crooked window gives it a storybook haunted-house look. I often mix two shapes so the light pattern feels more natural at night.
Safety first: Use only a battery LED candle inside this project. Cured expanding foam is flammable, so this is strictly a flameless lantern.
Best display spot: This lantern looks especially good on porch steps, beside a potted mum, or tucked into a Halloween table centerpiece. The flicker reads best in low light, so dusk and evening are where it really earns its keep.