I wrote in April about overwintering some pots in my attached, unheated, garage last winter. They look pretty good! So, I thought today I'd list what was in these pots that survived.
A note about conditions: the pots are about 14+ " across, and they are lightweight plastic and/or whatever that stuff is that's popular in the fake pots they're selling these days.
The garage temperature depends on what it's doing outdoors - the two older cats sleep out there except during the very worst weather. If their water starts freezing over, they stay indoors. The cat water froze several nights and even froze solidly a few nights, so I know the temps went pretty low in an on and off pattern.
I watered sparingly about once a month. I heard a good idea that I'll use next year, ice cubes.
There is a shop light on the ceiling we have on many days, but the main light is a low northeastern sunlight from a small window.
So here is what survived (or not):
SURVIVED
thyme
lemon thyme
rosemary
parsley (I know, a biennial, but before it bolts, the second year, it's still good)
a volunteer dandelion
tricolor sage
purple leafed sage
bronze fennel
green santolina
NOT
of course the tender stuff: basils, pansies, ornamental peppers, stevia.
The herbs look good and they are ahead of plants that were in the ground, but I'm not sure of how dependable it is to try to overwinter potted herbs for more than a few seasons. They will need repotting as the soil breaks down and loses its quality, I'm sure, just like houseplants.
Along the same lines, I've successfully overwintered other plants in the garage this way that were borderline hardy - a zone 6 rose (the poor dear, finally died from neglect, I think it needed repotting), a Japanese tree peony that is now planted in the ground, a boxwood, doing well, and several clematis that were waiting for the right spot, and some alpine strawberries in a glazed strawberry pot, which has cracked.
Cannas however, turned to mush, and clay pots need to be kept bone dry if frozen, otherwise, I've found, they unfortunately weaken and "shale."
The photo shows one with purple sage, thyme, lemon thyme and bronze fennel. I didn't "groom" it for the shot - the fuzzy white stuff isn't some strange fungus, it's cottonwood fluff from my neighbor's tree.
