The device can be sealed and waterproof. The LED strips already come with a silicone like sheath. I'll need to cap the bottom end, but I'm thinking of squirting some silicone into the bottom. Just regular caulk like material.
For the top part I got waterproof connectors, which makes it easy to disassemble, but since one has to wire the other side of the connector up, I wonder if it really is that much of an advantage to use any connector at all, other than if one wanted to leave the wire up year round but take the strips down or replace them occasionally? I'm not sure.
But an enclosure for the circuit board is necessary, and I guess that's why we need a waterproof connector. I first thought about shrink tube, but I don't know if I'll be able to find something large enough for the PCB but that shrinks enough to seal around the thin wire. My first experiment was a failure. Also, the shrink wrap was tight enough that it pressed the button permanently. So shrink tubing is not going to work.
My next idea is regular tube with caulk at either end. It won't be pretty but it will get me through the next round of testing, which will take place outside.