> Further research into the area might involve the nailing to the wall of a stronger jelly mix. Alternatively, the "wall" could be placed, nails first, into the jelly while it's setting, to allow the jelly to set around the nails. Then in the morning the bowl can be removed, leaving the jelly nailed to the wall.
Ahaha, but also, hmmm... thinking would it actually work if you allowed the jelly to set around the nails?
If you read further some commenters tried that and failed, along with setting straws into the jelly and nailing them and mixing solids into the jelly to improve the structural integrity. The results are only noted as mixed, so I assume they didn’t work out reliably.
I definitely have a few ideas: try smoother and surfaces to adhere to (does jelly suction to the surface?), set the jelly vertically in a box against the wall, try mixing cool whip into the jelly to thicken it…
Ahaha, but also, hmmm... thinking would it actually work if you allowed the jelly to set around the nails?