Yellowing Satsuki Azalea

[Francesco84]

Hi all! First post here and sorry to come with a problem but my entire satsuki was covered in all yellowish-green leaves about 14 days ago, which have now turned completey yellow and are starting to drop. That said, the leaves around each flowering bud have remained dark green and healthy. We had our first freeze in nyc a couple of weeks ago (25-30F for the night) and the day or two after is when I noticed the leaves turning yellow-greenish. Roots a bit on the dry side as well. I received the tree this summer from Delaware. No fall fertilization. Thinking maybe a stressed rootball with the combination of winter onset? Any thoughts would be greatly appreciated.

 

[Captain.Bonsai]

I’m not going to say it’s normal for your plant, but this can be normal for azaleas. They can be semi evergreen. 2 of mine do this... Yellowing and dropping leaves. The tips should stay green. The buds should remain where the leaves have fallen. The branches will be full of green leaves again next spring.

... or it’s dying. Ha!

 

[Pitoon]

It's shedding it's older leaves. I have one big azalea in the ground and another in a pot that are doing this right now.

 

[Francesco84]

It's shedding it's older leaves. I have one big azalea in the ground and another in a pot that are doing this right now.

Thanks for the note! Do you greenhouse or cold frame your potted azalea?

 

[Francesco84]

I’m not going to say it’s normal for your plant, but this can be normal for azaleas. They can be semi evergreen. 2 of mine do this... Yellowing and dropping leaves. The tips should stay green. The buds should remain where the leaves have fallen. The branches will be full of green leaves again next spring.

... or it’s dying. Ha!

Haha, thanks for the feedback. Exactly what I was thinking...

 

[Pitoon]

Thanks for the note! Do you greenhouse or cold frame your potted azalea?

The potted one is in the cold frame and the other is in the ground in front of my house.

 

[Meh]

I think you are OK, this happens to mine too. But here is a more authoritative source for you which may help:

Fall color on satsuki azaleas - Bonsai Tonight

Fall color on satsuki bonsai isn't a common cause for concern.

bonsaitonight.com

 

[Meh]

BTW, nice looking base on that tree.

 

[Adair M]

I bet it blossoms white, doesn’t it? If the flowers were pink or red, the leaves would turn red. And leaves that turn variegated indicate variegated flowers.

 

[Pitoon]

I bet it blossoms white, doesn’t it? If the flowers were pink or red, the leaves would turn red. And leaves that turn variegated indicate variegated flowers.

I noticed red leaves on one of my azaleas that blossoms a peachy color as well.

 

[shinmai]

Hi all! First post here and sorry to come with a problem but my entire satsuki was covered in all yellowish-green leaves about 14 days ago, which have now turned completey yellow and are starting to drop. That said, the leaves around each flowering bud have remained dark green and healthy. We had our first freeze in nyc a couple of weeks ago (25-30F for the night) and the day or two after is when I noticed the leaves turning yellow-greenish. Roots a bit on the dry side as well. I received the tree this summer from Delaware. No fall fertilization. Thinking maybe a stressed rootball with the combination of winter onset? Any thoughts would be greatly appreciated.

 

[shinmai]

Sorry about that, my tablet went dead.
I would caution you about exposing satsuki to temperatures below freezing. Remember that cold-hardiness temperature guidelines are for plants in the ground, not in pretty little pots. Satsuki are rather sensitive to root temperature, either too cold or too hot. I lost a dozen or so in January when I was traveling and we hit 27 below, and the guy watching my greenhouse waited overnight to tell me that the temp in the greenhouse got down into the low twenties. Adding a second space heater got the temp back up to 37, but the damage was done
Rhododendrons generally, especially azaleas, are vulnerable to catastrophic damage if they freeze and then abruptly thaw. It can cause the bark to split through the cambium. The azalea society website will tell you that azaleas virtually never survive a freeze-induced bark split.

 

[0soyoung]

I bet it blossoms white, doesn’t it? If the flowers were pink or red, the leaves would turn red. And leaves that turn variegated indicate variegated flowers.

What does it mean if the leaves just stay green?

 

[Adair M]

What does it mean if the leaves just stay green?

It mess as me you live in a really mild climate where the tree doesn’t have to go dormant!

 

[Adair M]

Sorry about that, my tablet went dead.
I would caution you about exposing satsuki to temperatures below freezing. Remember that cold-hardiness temperature guidelines are for plants in the ground, not in pretty little pots. Satsuki are rather sensitive to root temperature, either too cold or too hot. I lost a dozen or so in January when I was traveling and we hit 27 below, and the guy watching my greenhouse waited overnight to tell me that the temp in the greenhouse got down into the low twenties. Adding a second space heater got the temp back up to 37, but the damage was done
Rhododendrons generally, especially azaleas, are vulnerable to catastrophic damage if they freeze and then abruptly thaw. It can cause the bark to split through the cambium. The azalea society website will tell you that azaleas virtually never survive a freeze-induced bark split.

The Satsuki from Northern Japan are more cold hardy than the ones from Southern Japan.

The Northern ones will have smaller, more pointed leaves. Whereas the Southern ones will generally have larger and the leaves will be broader.

There are hybrids, I’d treat those as “Southern”.

Satsuki have always been cold hardy in my area, but then again, I set them on the ground, and I have “Northern” varieties.

 

[rockm]

The Satsuki from Northern Japan are more cold hardy than the ones from Southern Japan.

The Northern ones will have smaller, more pointed leaves. Whereas the Southern ones will generally have larger and the leaves will be broader.

There are hybrids, I’d treat those as “Southern”.

Satsuki have always been cold hardy in my area, but then again, I set them on the ground, and I have “Northern” varieties.

Agree. Depends on the original source of the satsuki. I have a Shiro Ebisu satsuki bonsai that I leave outside all winter in a mulch bed. It has been fine with prolonged exposures to temps as low as single digits in the last few years. I got lucky, as I only heard about the North/South satsuki hardiness thing after I had my tree for a year and had wintered it outside.

I heard about the differences from friends who run a bonsai nursery. They look after a large collection of imported, old, well-developed satsuki bonsai in the winter. The owner of those trees caught the satsuki bug and travels to Japan most every year to work at satsuki bonsai nurseries. Every year, he has imported mind-blowing satsuki bonsai from those nurseries for his personal collection. In the first few years, he lost over 80 percent of stuff he imported. It stopped when he told his Japanese teacher about the depressing losses. The teacher asked about climate. The teacher had assumed Virginia was "hot" in the winter like a lot of the Southern U.S.

After the student told him that Virginia has sometimes stiff winters with temps well below freezing, the teacher said "no wonder" there were big losses. The student was buying "southern" satsukis that weren't cold hardy. The teacher started selling him "northern" varieties that are more cold hardy. Hasn't had a loss since.

 

[Meh]

Agree. Depends on the original source of the satsuki. I have a Shiro Ebisu satsuki bonsai that I leave outside all winter in a mulch bed. It has been fine with prolonged exposures to temps as low as single digits in the last few years. I got lucky, as I only heard about the North/South satsuki hardiness thing after I had my tree for a year and had wintered it outside.

I heard about the differences from friends who run a bonsai nursery. They look after a large collection of imported, old, well-developed satsuki bonsai in the winter. The owner of those trees caught the satsuki bug and travels to Japan most every year to work at satsuki bonsai nurseries. Every year, he has imported mind-blowing satsuki bonsai from those nurseries for his personal collection. In the first few years, he lost over 80 percent of stuff he imported. It stopped when he told his Japanese teacher about the depressing losses. The teacher asked about climate. The teacher had assumed Virginia was "hot" in the winter like a lot of the Southern U.S.

After the student told him that Virginia has sometimes stiff winters with temps well below freezing, the teacher said "no wonder" there were big losses. The student was buying "southern" satsukis that weren't cold hardy. The teacher started selling him "northern" varieties that are more cold hardy. Hasn't had a loss since.

This is very interesting. Is there any reliable source containing a categorization of northern v southern varieties?

 

[Pitoon]

This is very interesting. Is there any reliable source containing a categorization of northern v southern varieties?

By leaf shape and when they bloom

 

[rockm]

This is very interesting. Is there any reliable source containing a categorization of northern v southern varieties?

There is, but it's apparently in the heads of the growers in Japan, or at least in mostly Japanese-language literature. I've not seen a comprehensive list of varieties in English. Adair's description of leaf shape and size is what I've heard too.

 

[Meh]

There is, but it's apparently in the heads of the growers in Japan, or at least in mostly Japanese-language literature. I've not seen a comprehensive list of varieties in English. Adair's description of leaf shape and size is what I've heard too.

Thanks, there are some lists of varieties and hybridizations online but I've not seen anything on North/South origin.