How far can I Push the Temperature?

You know it's not as if I didn't know summer was going to end. %$#@ I do this every year!

I'm scrambling to get everything in as the temperatures are supposed to drop into the 40's during the night this week. Naturally I don't have everything ready so I'm plotting my priority order and since I'm pretty inexperienced with begonias I thought I'd seek the help of those who aren't. I have some beautiful canes that I want to bring in...how much cold will they take? I only had one plant last year and it seems to me that I didn't bring it in until right before the first frost, but I don't want to take the chance if I really shouldn't.

Will somebody please take pity on this poor procrastinating soul?

Begonias are fairly tough and can take light frosts if you don't mind sacrificing the leaves. If they are under trees or a roof then they can take even more cold than ones left out with no cover. But if you get into a hard frost then rhizomes (and I suppose canes) can be damaged significantly - not killed but not pretty either.

You could try a cover (plastic or cloth but try to keep it off the leaves). This should be good down to mid 20's but not for extended periods of cold (weeks of freezing weather). I did this many years ago while I was erecting a greenhouse at my last house. Nothing was killed but there were some begonias and other houseplants that had lots of damaged leaves. Plants that did not touch plastic came out fine.

Play it safe and take them indoors unless you want to experiment.

Thanks for responding Butch. They are definitely coming inside, but now I know that if I can't get them in for a few more days they'll still be OK. I think this cold snap is only supposed to last a few days and by then hopefully I'll have the EEs and the coleus all tucked in for the winter.

I know what you mean about changing weather. We usually get our first frost the end of October but then it turns warm again for a few weeks. Each year is different though so it is best to have a plan in mind on when to move everything indoors. I ran out of room and energy last year so I left most of my cactus and succulents outdoors last winter. Out of maybe 100 plants only two agaves survived.

Getting back to begonias I had severe damage on begonias in the front yard but hardly any damage on the ones under shade trees when we got a hard frost in early November 3 years ago.

Here is what happened to one of them (Caribbean King).

Here is what it looked like a couple of weeks earlier.

Oh my gosh that is so sad looking! But you say it surrived in the end?

I just got a very old, very small used greenhouse. The poor thing is riddled with cracks and crevices and I'm afraid that I have neither the funding nor the know-how to do much in the way of repairs right now. But I'm hoping that by hanging a few tarps on the inside of the worse walls at night I can use it as a "season extender." I may have to run heat every once in awhile, but the longer I can avoid bringing everything into my small dark cave (house) the better their chances of overwintering will be.

As with most of us plantoholics I want to save much more than I have room for so now the juggling begins. I'm trying to convince myself that it won't kill me to sleep standing up for 5 months. LOL.

I know exactly what you mean about space and trying to save everything.

All my begonias survived frost damage but were really knocked back. Some enjoy a cool darkish garage but C. King and Queen did not. They were half the size the next year. Benitochiba did great but I guess it has "rex" genes in it so it goes semi-dormant anyway.

I put a lot of my largest houseplants down on their side on top of flagstone under the deck, cover with a tarp, and weight it down. This is where they spend five to six months without a drop of water. A lot don't make it but a lot did. Experiments can have bad results as well as some pleasant ones too. Cordylines, some ferns, bird of paradise (stretlitzia reginae), variegated shell ginger, tree philodendron are a few of the survivors for instance.

Back to begonias, you could cut the size of the plant down and pot down, propagate the cuttings and give away, sell, or keep for the future. A couple in our begonia club starts new begonias indoors and if it gets too big it goes out in their small greenhouse.

As for your greenhouse, you would be better off repairing or caulking your cracks and holes than trying to hang a tarp. You could caulk shingles on top of the largest holes for instance.

When I had a greenhouse at our last house, I found that cacti and succulents and a lot of begonias could handle temps down to freezing or below overnight. Some begonias were too sensitive to cold and died. Some houseplants can't take that kind of cold either but there are a lot that can.

Hi Again,

How very interesting to hear about your adventures and misadventures. When the space is limited and the plants abundant I guess experimenting is our only choice. Unfortunately I have the added disadvantage to being a new gardner with much of my growing collection. There's much more experiment than experience with almost everything I've got.

As far as the greenhouse I really hate to start caulking. Most of the air leaks are at the window and door and if I break out the caulk (or any other "perminant" fix) it will hinder my ability to open and close them. Next year I hope to have the funding to fix it proplerly but for now I'm going to have to wing it. I just sealed up the window side with a double layer of plastic that i secured with good old duct tape. I did about 3/4 of the door the same way leaving just enough space for me to pass through. If it won't hold the heat well enough I'll just have to haul everything in earlier than I'd hoped. All I'm really looking for at this point is the ability to keep everything out an extra month or so.

Hi Lala,

I had a old small greenhouse in England where it can get very cold. I used to cover the glass walls and roof with bubble wrap, the one with the big bubbles. It helped a lot.

Hi Lala,
Thank you so much for bringing this topic and all the responses. I am a terrible procrastinator and have been biting my fingernails as the temp have gone down to the 40's at night here in St Louis.
I don't have a greenhouse but have a lot of room indoor and am planning on bringing many of my pots indoor in the next couple of weeks. I have started setting up some aquarium with lights for the ones that like more humidity.
I am glad to hear that begonias will do OK under trees ( where mine are now). Last year I did experiment by taking one cane in and left the sister plant outside. Of course it froze and never came back. So everybody is coming in this year!
For outdoor solution, some of the people on the heuchera thread suggested having a mini greenhouse by surrounding your potted plants with 4 bales of straw then covering with an old window. That seems to work for heucheras.

Heucheras are cold hardy though. If you can keep the surrounding temps above freezing a lot of begonias will survive so the straw bales may work but it's a big gamble too (drafts, rodents, strong wind, etc).

I planted several cane begonias in the ground at my last house (Sophie Cecile, Lucerna, Irene Nuss, coccinea) and cut the tops when Jack Frost came calling. All of the tops rooted except the coccinea (or something similar). The next spring one cane came back from the roots - it was coccinea - hallelujah. I now bring in all begonias before the first hard frost is announced. Light frosts are okay but the foliage will suffer.

It's going to frost here tonight, so all the begonias went into the greenhouse (over 100). They are going to winter over in our new sunroom, but the contractors are a month behind finishing the glass. It will be much warmer in there than the greenhouse. I'm heating with a pellet stove, so I'm concerned with the humidity level and the temp. The begonias are mostly canes, with some rexes and rhizos. Should I get a humidifier for the room? The temp will be in the 70's, maybe up to 80. It is 12' wide, 23' long and 14' high, all glass including the roof. The floor is slate and the house wall is brick.
Also, I usually cut the canes back hard to fit them into the greenhouse (which is 20 x 36 and crammed!), but will I need to do that if I have room in the sunroom? And will the rexes defoliate (though most have already - they don't like chilly fall weather) in this warmer room?
Any help with my new experiment is appreciated.

I heat my house with wood, and even with a kettle of water on the stove the air still gets too dry. (I have the chapped lips to prove it). I am going to get a humidifier for the house for sure. We will be building the attached greenhouse this coming week, we intend to heat it with air blown from inside the house. I heated my old GH with wood for several years, and with the dirt floor, and the tub with water plants I never had to humidify the air. I am hoping that having the dirt floor will provide the humidity I need for the GH, we'll see. In answer to your question--if you could find an inexpensive hygrometer that will let you know when & if you need to humidify the air.

Spider I like the bubble wrap idea. I used to have a great outlet for it too but I'm not sure where I'd find it now (at a reasonable price.)

The begonias are still outside and looking good. We've dipped down into the upper 30's a couple of times at night but generally it's still staying in the mid 40's. I know I can't hope for that much longer though so I'm getting plan B together today.

Unfortunately plan A (the greenhouse) is about full to capacity and I only have one decent window in the house which makes natural lighting a bit of a luxury here. I'm erecting some new shelves for the basement and now have to determine who gets the sunny window and who gets the artificial light. I have a bazillion house plants that need to come in too, and to be quite honest if something has to go I'd just as soon lose those as the begonias.

DB and Gran I'm anxious to hear how you make out.

I am liking the beubblewrap idea too--since mybig "plant window" does not have a storm window and I don't want my gesneriads to get a "chill"

Isn't the bubble wrap idea popular here in the US? In England, everyone who has a greenhouse use them as they help to keep the temperature higher than a heater alone.

Lala, I think your plants will be as good in the basement as the ones in the sunny window.

I met someone who grows most of her plants under artificial light and they are very healthy and beautiful.

We rented an old lap glass greenhouse before we built ours. My husband bubble wrapped the entire structure, and the oil use plummeted. I could not believe the amount that we saved.

Our local nursery chain uses a double greenhouse using plastic sheeting. The big greenhouse offers some protection from wind but is not heated except for the coldest days. Perennials, annuals, select shrubs and trees in bloom and leaf are displayed here. Then there is a smaller section with another enclosure (again simple plastic sheeting) for houseplants. It is like a sauna in there. Propane heat is used on the coldest days. This may not be practical for the home gardener due to the sizes of these rooms - especially the height of the roof (perhaps 24 to 30 feet tall), but the principle is the same - use of an air gap to provide more insulation (like double pane windows).

I've got a question for you bubble-wrappers. How do you attach it? As I previously stated I put plastic over the air leaks around the door using (you might be a red-neck IF) duct tape to hold it in place. Well I'm having trouble with the tape coming loose. I suppose temperature fluctuations and moisture are the culprits, but I'm wondering should I be able to get my hands on some bubble wrap how will I keep it in place?

There was enough moisture in the lap glass greenhouse that it just stuck to the glass.

Lala, I don't know about here in the US but in England they sell proper plastic clips that you attach the wrap to.

My greehouse had a wooden frame so i used the small drawing pins, the ones people use on cork boards.

Hi Spider,

Would you know where I would get these clips? I'm having trouble getting a visual on what they are so I'm kind of stumped where I would look for them. (Although I still haven't gotten the bubble wrap, LOL, but I'm hoping!)

Lala, they were for sale in England. I have no idea if you can find them here. I thhink the best way is to post something on the greenhouse forum. They must know all the tricks.;o)

;-)

Lala, did you find them?

Jane,

One of our members is attaching bubble wrap to the inside of their greenhouse with double sided tape. I think they can get some of their supplies from Charley's Greenhouse.

This is what she said:

"When DH retired 14 years ago he gave himself the greenhouse as a gift. We have had the insulation ever since but have never attached it. But with the high price of heating we are finally doing it. We bought it from the the company where we had bought the greenhouse (Turner). They warned us not to confuse it with the lightweight packing material.

I have also seen this product in Charley's Greenhouse and Garden catalogue. A roll 24" x 80 ft (160 sq ft) cost $49.95. In addition to that a double-faced adhesive tape is required for $10.95 for 108 feet."

We got our first killing frost a couple of days ago, but the begonias were covered and tucked into a corner of the house and survived just fine. They have since been moved to their new winter home in the basement, and now begins the long wait for spring. The GH however is still crammed to capacity with coleus and other assorted greenery.

Thanks again for any/all useful information. I love how you can pick up great tips on such a myriad of subjects just about anywhere you go on DG. I love the statement, "They warned us not to confuse it with the lightweight packing material," which leaves a novice like myself wondering if there is really that much difference or if they just want you to buy their product. LOL. I believe I will do a little investigating.

La
(Jane is perfectly fine but that is my middle name. I generally go by "La" or "Lala.")