Datura (Brugmansia) Trees - Winter Care in Canada (Zone 5)

[chief]

I have 20 trees (5-8' tall) that I have stored in a heated greenhouse in previous years and am looking for an alternative....
Is it OK to cut them back and store in an unheated, limited light, garage provided they don't get tempurature below freezing?
Re watering..will 3-4 cups every 2-3 weeks suffice ?
How about any fertilizer?
Should they be sprayed before storage? with what?
Thanks in advance for "expert" help on this one.....

[rainbowgardener]

My only claim to expertise on this one is that I have ONE of these trees that I started from seed (not easy!). It's about to come in for its third winter indoors. Since you have 20 of them (!), you probably know a lot more about them than I do.

But since no one else responded, I did find this article for you: https://www.gardeningknowhow.com/exotic/brugmansia-winter-care-wintering-brugmansia-in-your-home.htm

Here's the section where it seems to answer most of your questions:
Once temperatures drop below 50F outside, it is time to take steps for wintering brugmansia. Place the plant in a dark, poorly lit location, such as the basement or even a closet, for winter storage. Less light and cooler temperatures (above 40 degrees but under 50) are important for dormancy. Continue to water brugmansia sparingly, about once a month, to prevent the plant from drying out completely. However, do not fertilize it. Allow brugmansia to enter dormancy as normal. Complete leaf drop during this time is normal for brugmansia over winter.

Last winter I tried growing mine as a houseplant indoors, with lots of extra (artificial) light. It gradually over the winter-early spring season lost all of its leaves anyway, so that by the time I could finally put it out again, it was bare. I think I won't bother with that again.

The article also talks about cutting them back. Have you done that with yours? I'd be afraid to....