I used to have two hoophouses in my backyard each winter, one kept above freezing and the other one not heated at all. I used the unheated one to store potted plants that could take the freeze but looked awful on the patio as well as potted bulbs. I did this to keep the squirrels out of them.

I use the barely heated one to store potted citrus trees and tree ferns - anything that can take cold weather but not freezing. It is surprising how many "tropical" plants respond better to a cool period over the winter. Things like orchids and orchid cactus and bromeliads seem to bloom better in the warm parts of the year if they have a cool period before it.

I used space in each of them to store baby trees that are a bit tender their first couple of years (from seed or rooted cuttings). Those plants are now larger and planted out in the yard so I no longer need two hoophouses - I only use the large one now and I keep it above 32.