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applestar
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Re: Minimum Night Time Temperatures - bringing plants inside

It was officially 47° f this morning... Which means it probably went down to 45°F in my garden.

...but all my container plants are still out there... :eek:

I'd brought the orchids to the back door yesterday, but forgot to bring them inside. At least they were a bit more sheltered on the brick patio than they would have been.... :|
(Chenille Plant is hanging out in the middle of the back yard shepherds crook.... :roll: )
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MrBote
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Re: Minimum Night Time Temperatures - bringing plants inside

I group my containers during (don't laugh) freeze warnings/cold fronts in Florida. I have a snap together hoop (pvc pipe) tent that takes a lot less time than moving the plants. Then it's just a matter of putting a couple clamp on shop lights with the metal shades in there with them, turned upside down on something flat so that it is still dark, yet there is some ambient warmth created in there that can up the temperatures by 10 degrees or more. I have 8 shop lights with 27w-100w equivalent daytime cfl bulbs and during the day, if it's overcast following the cold front, I can concentrate some growing light on some of the more sun hungry plants, which seems to help keep things going as if there was no cold at all.

I have managed to buy myself a month or more growing season by this practice. Now I have a heating pad, and a 250w HPS grow light for extended periods of overcast conditions, so that at least the more sun hungry plants don't slow down. I simply exchange the power usage for something like the water heater, and other parasitic power consumers around the home.

Of course I have a much more mild growing climate than most here likely, and I can now get by without lights/heat since my climate ends up being ideal for cool season crops anyway but, before I knew the difference, I did manage to pull it off without moving my plants indoors. If I lived in no man's land, like many of you do, I could see myself extending a growing season by at least a month or more. I know this is no new news, just that I managed to make it work with Spring time vegetables and other sensitive tropical plants here without a whole lot of moving things. We did get some extended freezes into the teens and 20's some years.

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YourMoveKaiba
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Re: Minimum Night Time Temperatures - bringing plants inside

I had issues earlier in the spring with night time temps.
I have a 16 year old hibiscus tree that had some sentimental value to me and when I moved to my new apartment last December the plant was not happy at all so i couldn't wait for warmer weather so I could bring it out into the sun. For a couple weeks we were having like 70 degree days so I moved my plant outside and didn't even think about the temperature drop at night (I'm new to gardening. Never done it on my own before) and my poor tree almost died.

I lost a good portion of the tree due to this, it's hardly a tree anymore. But my hibiscus is a fighter and it's slowly working it's way back. I'm not making the same mistake twice and I now use a plant lamp to make sure my tree gets enough sunlight, at least until next year when it is stronger.

My window box of tomatoes and banana peppers on the other hand have been fairing quite well, but I am watching them like a hawk now after my experience with my tree lol

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GardeningCook
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Re: Minimum Night Time Temperatures - bringing plants inside

While any tropical-type container plants come indoors as soon as night temps are slated to dip into the 40's, others don't get an indoor respite unless night temps are supposed to go below 20 or so.
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Francesco Delvillani
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Re: Minimum Night Time Temperatures - bringing plants inside

applestar wrote:It went down to 52ºF last night!! :shock:
I forgot that I need to automatically subtract 2~3º from the official forecast for cooler temps to ajust for my garden's microclimate (unfortunately this rule doesn't apply when it's hot :?)

I'm a bit worried about some of my plants outside, but it's really WAY too early to think about covering them or bringing the container plants in. :roll:

These are what I have in my notes for Minimum Nighttime Temperatures. I posted the first set, maybe 2nd set too, before in response to someone's thread, but I wanted to start a new thread and ask you all for opinions and contributions. The first set is temperatures at which the plants will stay healthy. The 2nd set is temperatures that the plants can "survive" and "recover".

The USDA zone hardiness implies that the plants will lose foliage and go dormant before temps drop to those minimum temps, so to avoid dormancy, they need to be brought inside earlier -- at least 5°F higher than the minimum, I think. I've left them out to near minimum and they drop leaves/die down and sulk for a while, which can lead to panic -- "Oh no! I killed it!"

So let me know what you think. Post corrections and additions and let's see if we can turn this into a handy reference guide. :wink:

MINIMUM NIGHT TEMP:

Peppers

- ideal daytime temp of 75°~85°F and night temp of 55°~65° F Max 100ºF
- After transplanting, the optimum temperature is approximately 23ºC (73ºF) by day and 18-21ºC (64~70ºF) at night. Minimum soil temperature 20ºC. Max day temp 35ºC (95ºF) - dormant until lower Fall temp.

Eggplant

- ideal daytime temp should be in the range 80°~90°F and night temp should not go below 60°~65°F. Growth retarded at 60ºF

GROWTH STOP/Enter Dormancy Threshold TEMP
------------------------------------------------------
Basil - 60ºF
Eggplant - 60ºF
Pineapple - 60°F
Stevia - 60°F
Banana, Super
dwf. cavendish - 55°F
... BANANA minimum ...
Warmth, but not too much or too little! Specifically, growth stops and heat stress will occur at 100 degrees Fahrenheit (38 C). On the other end of the scale, a temperature below 42 degrees Fahrenheit (6 C) will cause leaf chlorophyll destruction. Freezing is obviously not a good thing for a banana plant, but the underground rhizome may survive if the cold temperature period if brief. Kiss the leaves goodbye, though.
https://www.sherrysgreenhouse.com/oldsite/banana.html
...
Coffea arabica - 55°F
Peppers - 55ºF
Zinzibar officinale
(edible ginger) - 55°F
Tomato - 50ºF
Nasturtiums - 48ºF

--

I also have the following in my notes:
**Bring inside at least 5°F above highest zone temp to AVOID dormancy**
Based on USDA Hardiness Zone Map at https://www.usna.usda.gov/Hardzone/hzm-nw1.html

BRING IN ABOVE 60°F
-------------------------
Orchid 55 ~ 60
Chenille plant 55 ~ 60
Coffea arabica 55 ~ 60
Jasmine, Maid of
Orleans 9 (20) ~ 11 (40)
Pineapple 10b (35) ~ 11 (40)

BRING IN ABOVE 55°F
-------------------------
Basil 50
Banana, Super
Dwarf Cavendish 40

BRING IN ABOVE 50°F
-------------------------
Lemon, Meyerii 10a (30) ~ 11 (40)
Norfolk Island Pine 10a (30) ~ 11 (40)

BRING IN ABOVE 45°F
--------------------------
Aloe vera 10b (35) ~ 11 (40)
Grapefruit 10b (35) ~ 11 (40)
Lime 10b (35) ~ 11 (40)
Lemon Grass 10b (35) ~ 11 (40)
Night Blooming
Cereus 10b (35) ~ 11 (40)

Lemon 10a (30) ~ 11 (40)
Mango 10a (30) ~ 11 (40)
Rubber Plant 10a (30) ~ 11 (40)
Jalapeño 9 (20) ~ 11 (40)
Stevia 9 (20) ~ 11 (40)
Geranium 9 (20) ~ 11 (40)


BRING IN ABOVE 40°F
--------------------------
Avocado 10a (30) ~ 10b (35)
Lemon Verbena 9 (20) ~ 10b(35)

Fuchsia 9 (20) ~ 10a (30)

Pineapple Sage 8 (10) ~ 11 (40)
Fig "Petite Negra" 8

BRING IN ABOVE 35°F (frost warning)
------------------------------------------
Rosemary 7a (0 °F) ~ 7b (5 °F)
Parsley 7a (0 °F) ~ 7b (5 °F)
Thyme, VarLemon 7a (0 °F) ~ 7b (5 °F)

(DORMANT STORAGE IN GARAGE ABOVE 28°F and foliage drops)
Pomegranate 10b (35) ~ 11 (40) <-- allow to go dormant
Overwintering
Hot peppers <-- allow to go dormant
Pineapple Sage
Venus Fly Trap (store dormant in cooler for insurance)
These temperature refere to a medium temperature.....If, in the early morning, you have lower temperature but during the day you have sun and warmer T they'll not go in dormancy....

Anyway, some tropical trees you listed can go in dormancy without losing their leaves and without dying....

P.s.

Also Fig can go to dormancy, is not different from Pomegranate :D
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applestar
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Re: Minimum Night Time Temperatures - bringing plants inside

Argh! Weather caught me unready! 51°F at dawn this morning and my orchids are still out there. Gonna lose some leaves for sure (grumble) -- I hope today's forecasted high of 83°F will help like FD said.

Some of the plants in my list that need to be brought inside for the winter are too big and/or can handle dormant overwintering. With those, I let them go dormant and keep them above 25°F or above in the garage with some supplemental light and kept nearly dry. I'm going to have to try using this technique (but kept somewhat warmer aa maybe in the 30's to 40's)with my so called "Super Dwarf" Cavendish banana this winter since the plant is WAY too big.

-- all my "Bring in above 60°F" plants are still out there and I was noticing a little color loss in the Coffee just yesterday, too. I can't let that one get stressed because it's currently loaded with nearly full sized berries.
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applestar
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Re: Minimum Night Time Temperatures - bringing plants inside

It's time for me to start thinking about this in reverse. In the list (which I realize might need to be reviewed and updated), the zone and temp info indicates absolute minimum temperatures these plants can withstand, and only when acclimated and in dormant state.

The temperatures at which they can go back outside will depend on what kind of temperatures and condition the plants were OVERWINTERED. Some can go out during the daytime but may need to be brought back in at night. Most of my plants in biggest pots won't go out until after frost and settled high enough night time temps for this reason, but if you are willing and can move them out and in, some plants will benefit. (But some plants e.g. ficus and hibiscus are fussy and will not like constantly being moved)

In all cases, they need to be gradually acclimated to full sun/wind and should start out in light shade or full shade and gradually moved out into ideal sun exposure.

If anyone has additional info on the listed plants or additional plant to add to the list, please post details and I will add/edit the first post so they will be immediately available for quick reference. :wink:
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Peter1142
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Re: Minimum Night Time Temperatures - bringing plants inside

I really don't think it is so simple. For instance, my Hansel and Galine eggplant and Ace and Biscayne peppers have no issues with nighttime temps down into the 40s. Also if the soil is warm it keeps the plants warm, and the duration of the low temp matters also, all night or several minutes is a huge difference. If I did not plant until nighttime temps were always above 60F it would not be possible to grow these things here. Minimum soil temps are far more important IMHO but that still varies based on variety and plant size etc.
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applestar
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Re: Minimum Night Time Temperatures - bringing plants inside

Oh oh! No, no. This is for mature Container Plants. I realize not many posts are made to this sub-forum, and right now getting ready for the veg garden is more on everyone's mind. Temperatures for planting SEEDLINGS into the ground is a whole different set of circumstances.

Peter1142, I realized what part of the list you were responding to. I'm adding your comment under the eggplants in the first post. :wink:

I think the temperatures for planting out seedlings is discussed individually and especially with reference to hardening off in many different threads, but we really need a well organized sticky thread for referencing in the Vegetable Gardening or maybe Seed Starrting forum. Maybe you could start a thread about it? It sounds like you have some good ideas.
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Peter1142
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Re: Minimum Night Time Temperatures - bringing plants inside

Ah I responded without reading carefully. I agree container plants are a different animal. Maybe I will make another topic. :)
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ButterflyLady29
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Re: Minimum Night Time Temperatures - bringing plants inside

So how did your orchids fare after that chill last year?

I've left citrus trees outside but covered on nights when frost is predicted. They get brought in only when the day was cold and cloudy and overnight lows are around freezing or on warm, sunny days when a freeze is predicted.

The most beautiful nasturtiums I've ever seen were in a container at a park in Alaska when the nights were close to but not quite freezing.

I don't see amaryllis on your list. I bring mine in when the temp is predicted to go below 40 F. And lantana will tolerate a frost without losing very many leaves, found that out by accident last year.

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applestar
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Re: Minimum Night Time Temperatures - bringing plants inside

Time to bump this thread. Sorry I didn’t respond to earlier queries — seems pointless to do so 2-1/2 years later, but the orchids are all still alive.... they might even have bloomed better after their chill.

Lately, I am more about letting plants that can be pushed into dormancy go dormant for less care overwintering strategy, while keeping those true tropicals from getting too cold and sulking. Some of the container peppers I want to bring in are already yellowing — I think from the recent chills.

I have a low 40’s forecast coming by the end of this week, even though the forecasted high for Wednesday is 91°F.
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