Strawberries benefit from chilling over the winter with some varietys tolerating more cold than others. If you purchased yours from a local nursery they were probably bred for your climate and in all likelihood will tolerate and actually benefit from over-wintering in your unheated greenhouse.

If you were growing the plants in soil I would advise you to stop applying fertilizer as soon as the cold drives them to dormancy. I suspect this will also be true for growing them hydroponically. I have no idea how they'll react if the roots freeze while suspended in solution.

Hope this helps,

SH

Thanks slaphead for the reply. I live in zone4, where it gets anywhere from -20 to -40 below zero, and I have stopped the nutrients about 3 weeks ago. I realize strawberry plants need chilling, but this would be like throwing them in the freezer. I would think this would kill the roots, but don;t know for sure??. I guess I will have to take my chances, and see what happens next spring. Thanks again for the reply, and have a Happy Holiday Season.

Grampe

I came across this link this morning. They suggest:

"Â simulate a winter for your new seedlings. Dip roots (or plugs) in microbial solution, gently wrap them in clear plastic and refrigerate them for two to five months. After this rest period, your transplants are ready to be added to your hydroponic system."

They have a bit of info on hydro strawberries  just scroll down the text.

Here is a link that might be useful: How to Grow Strawberries

Thank you very much Baci and slaphead for your reply. It has already gone to -7 below 0, and my strawberries are well frozen by now. I have left the plants in my containers, and will wait for spring to know the results. The plants are very well developed, and I know they don't mind the cold, so we will just have to wait and see the results. It seems like I just got things cleaned up, and have to make up some new bato buckets for some other experiments for the up-coming season. Again, thanks for replying to my question, and have a very wonderful Holiday Season,

Grampe