How to overwinter azalea?

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I've only owned one azalea so far, and for the past two years I've honestly just brought it to the nursery to overwinter, simply because it was made out to be extremely difficult to do on your own in terms of controlling the temperature and moisture levels. To the extent that I was told that people use digital meters that ping their phones at certain temps or humidities. I don't even know if the guy worked for the place, to be honest, but he made it out to be very difficult / nigh on impossible to do without dieback or some other calamity.

Do those of you who have had success with azaleas in pots in colder climates have any advice in terms of what you do? It was described as different enough that I was surprised I didn't find any threads when I searched, and figured I might as well make one in the event that it's useful to others as well.
 

Carol 83

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I overwintered a Chinzan in my unheated, detached garage last year. It did fine and bloomed like crazy. I'm hoping that it will work again this year, because I have quite a few more azaleas this year.
 
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I overwintered a Chinzan in my unheated, detached garage last year. It did fine and bloomed like crazy. I'm hoping that it will work again this year, because I have quite a few more azaleas this year.
I mean, that makes sense to me, but I figured maybe there’s something I don’t know haha
 

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Hmm, I think usually they're described as requiring some extra protection in our area but that's put me off from getting any myself. So I can't speak from experience.
 

Leo in N E Illinois

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@badatusernames - @Carol 83 - Carol's climate is quite similar to yours, follow her advice, it really is that simple. Most Satsuki are winter hardy to zone 7b or 7a, so it does not require a great deal of additional protection to get good results. You will get better results giving your Satsuki a cool to cold winter rest, as Carol does. If you keep Satsuki too warm in winter bloom will be more staggered, extended out over a longer period of time, and likely with few blooms overall. Treated as a tropical, Satsuki will decline over time. Best results are to give them a cold rest. An unheated garage or even a tool shed in zone 6b will be enough protection to get through the winter. An attached garage is okay too, if you put the Satsuki against an outside wall, near the floor, to get the colder location in the attached garage.
 

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Shohin
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@badatusernames - @Carol 83 - Carol's climate is quite similar to yours, follow her advice, it really is that simple. Most Satsuki are winter hardy to zone 7b or 7a, so it does not require a great deal of additional protection to get good results. You will get better results giving your Satsuki a cool to cold winter rest, as Carol does. If you keep Satsuki too warm in winter bloom will be more staggered, extended out over a longer period of time, and likely with few blooms overall. Treated as a tropical, Satsuki will decline over time. Best results are to give them a cold rest. An unheated garage or even a tool shed in zone 6b will be enough protection to get through the winter. An attached garage is okay too, if you put the Satsuki against an outside wall, near the floor, to get the colder location in the attached garage.
While you're thinking about it, could you just leave zone 7 plants out until it's projected to get too cold, then bring them in and grow them indoors ("early spring" for them)? Wondering if part of winter is long enough for their dormancy.
 
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@badatusernames - @Carol 83 - Carol's climate is quite similar to yours, follow her advice, it really is that simple. Most Satsuki are winter hardy to zone 7b or 7a, so it does not require a great deal of additional protection to get good results. You will get better results giving your Satsuki a cool to cold winter rest, as Carol does. If you keep Satsuki too warm in winter bloom will be more staggered, extended out over a longer period of time, and likely with few blooms overall. Treated as a tropical, Satsuki will decline over time. Best results are to give them a cold rest. An unheated garage or even a tool shed in zone 6b will be enough protection to get through the winter. An attached garage is okay too, if you put the Satsuki against an outside wall, near the floor, to get the colder location in the attached garage.

Perfecto, thank you for confirming!
 

rockm

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I've only owned one azalea so far, and for the past two years I've honestly just brought it to the nursery to overwinter, simply because it was made out to be extremely difficult to do on your own in terms of controlling the temperature and moisture levels. To the extent that I was told that people use digital meters that ping their phones at certain temps or humidities. I don't even know if the guy worked for the place, to be honest, but he made it out to be very difficult / nigh on impossible to do without dieback or some other calamity.

Do those of you who have had success with azaleas in pots in colder climates have any advice in terms of what you do? It was described as different enough that I was surprised I didn't find any threads when I searched, and figured I might as well make one in the event that it's useful to others as well.
I overwinter my shohin-sized imported Shiro Ebisu satsuki in the backyard, under mulch. It freezes constantly from December to March--it retains leaves over the winter and those sag during freezing and perk back up when it gets above freezing. Haven't had an issue with it in ten years now...I have to watch to insure the soil doesn't dry out--but exposed to rain and snow that has only been a problem once or twice over the years.

FWIW, I have posted before that there are "cold climate" satsuki varieties and "warm" climate satsukis. It can be depressing to try and overwinter the warm weather varieties in cold climates. I know that has given satsukis a bad rep in colder climates. I don't have a list of colder climate satsuki varieties, but Shiro Ebisu is one...
 

Deep Sea Diver

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@badatusernames - @Carol 83 - Carol's climate is quite similar to yours, follow her advice, it really is that simple. Most Satsuki are winter hardy to zone 7b or 7a, so it does not require a great deal of additional protection to get good results. You will get better results giving your Satsuki a cool to cold winter rest, as Carol does. If you keep Satsuki too warm in winter bloom will be more staggered, extended out over a longer period of time, and likely with few blooms overall. Treated as a tropical, Satsuki will decline over time. Best results are to give them a cold rest. An unheated garage or even a tool shed in zone 6b will be enough protection to get through the winter. An attached garage is okay too, if you put the Satsuki against an outside wall, near the floor, to get the colder location in the attached garage.
I'd say the main issue not covered to be aware now that you have the above information is moisture loss. A secondary one is fungus. Moisture loss is usually caused by low humidity, wind drying and exposure to sunlight, or a combination of the above, especially when the roots are frozen and can't replenish the water loss in the leaves and bark.

In a garage setting, the two water loss issues are low humidity and sunlight. Even @Leo in N E Illinois, who overwinters azalea in a well house, has to water his trees lightly at least monthly to maintain an appropriate moisture level.

A very small fan to move the air and avoid fungus in your garage may be in order for your situation too. I don't know if @Carol 83 employs one. However Chinzan (a sport of Osakazuki) is known as a winter hardy cultivar... maybe that's why so many of these are marketed?

The Kozan family of satsuki (Nikko, Kozan etc) is known as having cold tolerant cultivars as is Osakazuki, Kinsai and Matsunami (and their sports) to name a few. The flip side of the coin is these cultivars don't like hot days above 80F, so perfer to be sheltered for the afternoon and misted in the summer warmth.

btw: some folks think it is a myth that there are cold tolerant and warm tolerant varieties of satsuki, (often indicated by narrow leaves / pointed tips and rounded leaves / esp. rounded tips). The vast majority of the data indicates otherwise.

Cheers
DSD sends
 

JudyB

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I overwinter my Kozan in the cold greenhouse, I do use heat mats to keep the roots above freezing, but keep the air temps as close to 30 as I can. So if you have a place to winter it and are worried about low temp dips, maybe you could employ some sort of bottom heat. I don’t know if it’s necessary for Kozan, I have heard they are one of the hardier types, but I play it safe.
 

Carol 83

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A very small fan to move the air and avoid fungus in your garage may be in order for your situation too. I don't know if @Carol 83 employs one. However Chinzan (a sport of Osakazuki) is known as a winter hardy cultivar... maybe that's why so many of these are marketed?
I do not currently have a fan in the garage, but since I will be overwintering quite a few more this winter, perhaps one is in order.
 
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