Trying to control disaster!

Need some quick help! I have a solar greenhouse and use an electric heater with thermostat for nighttime heating. I try to keep the temperature around 45 degrees minimum. The power went out overnight and the temperature got down to 29 degrees inside the greenhouse. We have our power on again and it looks like I've lost about a dozen plants and there are another 20 that I cut way back because the leaves turned black. The stems show green still, so I'm hoping the frozen leaves and stems I cut off didn't ruin the plants. Is there anything else I can do to make sure they don't die off? Water with warm water? Feed them? Another question - clay pots seem to hold onto the cold overnight temps longer than the plastic. I was hoping they would hold on to the heat longer, but it doesn't seem to work that way. Anyone else have that experience?

I would stop cutting things back--they are actually better off if you leave them alone (the dead parts will protect the still living parts if you have another incident like this, plus it may turn out the parts that look dead now really aren't and would have come back in the spring). Since it was just the one night and the temps didn't get that far below freezing chances are most of your things aren't actually dead so I'd wait until spring and see what happens, you'll probably be surprised at what comes back for you. There's really not much you can do to improve their chances (besides getting a gas heater as a backup in case this happens again). I definitely would not feed them, and I would only water them if they need to be watered--and keep in mind that plants with a lot of damaged foliage aren't going to need as much water as they did before.

Where'd the power go off in St Louis? Last week, in south county?

I agree with ecrane 100%. No need to panic, it won't do any good at all. Stop snipping and wait a bit. Plants are usually tougher than you think. ;)

Thanks for the advise. I've calmed down and reassessed. We blew a fuse in our garage and breezeway , from which my greenhouse gets power. So, we lost power in part of our house and greenhouse, not our whole house. Problem was, I didn't know about it right away so the greenhouse got down to29.

When I walked out to the greenhouse I was greeted by black leaves on my hibiscus plants, bouganvilla. Thye stems were brown down part way and that's what I cut back. I left as far up as the green stem went and there were a few leaves that were not damaged. I think they will be ok. I lost most of the coleus The stems looked to be frozen an the leaves had already shriveled up. The coleus were much more sensitive to the cold than anything else. I was growing tomatoes and they died also. The other succulents and various other plants look ok now. Guess time will tell. Gives me something to do this week. I'm cleaning up dead leaves everywhere and moving things around a bit to keep an eye on the damaged plants.

Are you sure it only got down to 29? I've left hibiscus outside for the winter and grown bougies outside, and it takes either colder temperatures than that or multiple nights of exposure to temperatures in that range for those kind of symptoms to show up. And I have some coleus on my front porch right now that have already seen at least 3-4 nights in the last couple weeks down to 29-30 and last night was 28 and they're still fine.

My GH has gotten down to 29 twice so far. Once because it got colder than the weatherman said and I didn't light the heater. Second because the heater ran out of gas. I lost nothing. No burning of leaves or anything. I agree with ecrane, it must have been colder than 29. I have butterfly bushes in pots and bougies outside that have withstood the many nights of below 32 that aren't in my greenhouse. They are fine too.

At any rate, I'm sorry you had that happen. I know it can be upsetting to see your plants devastated by cold. I don't cut frost damage until spring. The plants look ugly, but it's the best. I'm sure your plants will come back in the spring.