That's a lot of seedlings! About half of my year old seedlings didn't go dormant so I ended up keeping them under lights. If they have gone dormant I don't see why you couldn't store them bare root as long as the roots didn't dry out. Can't your plumies stay out year round in your zone?
Karyn

Karyn, I heard that seedlings wouldn't go dormant in the first year. This winter will be their 2nd. winter as I sowed them around this time last year.
All Plumerias in my zone go dormant.
Boom

I'm curious why one would pull them out of there pots and store bare root. I don't have near as many, but I do have a few. Had planned on just keeping them on a heat mat under a grow light.
Lauri

Lauri how long do you keep your seedlings on a seed mat? I only keep them on the seed mat for the first month or so after they sprout and that's only during the winter.
Karyn

I've had them on their for...hmmmm.....well, months I suppose. I figure the longer they are on there the better their little roots grow. Maybe I should take them off? Hunh, good info goin' on here so it seems!
Lauri

I had year-old seedlings last fall that I kept under lights. Most remained green, but some dropped leaves, so I left them under the lights, but reduced watering. I think with seedlings you need to be prepared to keep them growing, but they'll tell you when they're ready for a rest. This year some of these now second-year seedlings are quite large -- almost 20" and will most likely go dormant.

My 2nd year seedlings had better go dormant this year. I won't have anywhere warm to keep them and like yours many are 2' and over. If they don't willingly go dormant can I just cut off the foliage and force them into dormancy without killing them?
Karyn

Good points everyone, thanks. I think I will end up keeping them in a greenhouse like last year. However, if some of them go domant. I might do experiment with storing them bare-rooted.
Boom