Hi Tina,
At this point I'd wait until it's warm outside to pot them in soil. I've put cuttings that have been in water for months outside in the spring with no problem but when I potted well rooted cuttings and had to keep them inside for extended periods I lost more than a few. I have no idea what the reason is and maybe it just happens to me. Now I either pot them soon after the nubbies have developed or I wait until it's time to go outside.
Karyn

I agree with karyn1 that you will have a better chance after any frost has passed. It seems that marsh type plants (ones that live in water) don't need as much sunlight as soil terestrial plants. I am posting an old yet informative link from the botany forum that has a lot of good Q&A and another link on the subject of water rooting plants vs soil. I really don't let my brugs get long water roots anymore. It was fun to do at first because it is fun to watch them grow. Now I just let them get nubbbies then pot them up in well drained soil. Place under grow lights (or sunny window), on a heat mat, and water alot at first then slowly back off. Misting the leaves seems to help alot too. I think I have better luck outdoors in indirect sunlight when they are adjusting than indoors though.
~SJN

Here is a link that might be useful: Q&A on Water & Soil Rooting

I am with Karyn and SJN on this one. I started mine in water and planted them in soil as soon as the nubbies appear. They are doing great and I actually recently up-sized the pot because the roots were coming out the holes in the bottom. I think you should plant your's when the temperature is consistently above 40 degrees. I may trim some of the roots too but I don't know if that is appropriate for Brugs. Any one knows?

Nixon

Nixon I haven't root pruned brugs but I know that people do it. Brug pots that have been sunk are root pruned if they are lifted for the winter. I'm pretty sure (but not positive) that some foliage needs to be removed also when you root prune.
Karyn

Definitely remove foliage when root-pruning! I only root-prune plants that I lift for winter, and on those I remove pretty much all the leaves, since I don't want to risk bringing pests indoors on them.

I was also told that the water roots are more fragile but I don't know if it is true since I never really let the cuttings I have fully root in water. If it is so, you'll want to be careful when you pot them so as not to break too much of the roots.

That reminds me of something I read on the ABDS site on rooting. It says you can trim the water roots without trauma to the plant. Here is the link. I dont think I have intentionally trimmed them but have accidentally broken some off -they do seem more brittle.
~SJN

Here is a link that might be useful: ABDS rooting