Browning leaves on satsuki azalea

[arctic107]

Hi!

I have 2 satsuki azalea, 1 35-year old tree and another, unknown (but obviously younger tree). I didn't water on Friday, August 23 because the temperatures have been cooling down here in Washington DC and I was worried about overwatering. On Saturday, temperatures were starting to increase and the trees looked a little dull so I watered twice. This morning, the younger satsuki azalea looked great and as it has all summer. I came back to the tree around 4pm this afternoon to see the tree looking like in the attached picture.

Did I accidentally overwater the tree yesterday and this morning?

Thanks!

 

[Glaucus]

So it looked perfect this morning, but you did water it twice, which is way more often than usual, and now it has this acute damage? And you saw no limp foliage? Like the part where it is brown now?

 

[arctic107]

Yes, it looked perfect this morning. No limp foliage and the branches are nice and springy.

 

[arctic107]

The brown leaves don't feel limp or mushy. They feel crispy.

 

[Glaucus]

When did you fertilize?

 

[arctic107]

I fertilized it 2 weeks ago tomorrow.

 

[arctic107]

I used 4 capful of Neptune's Harvest Fish Emulsion fertilizer in a 1 gallon watering can and watered until the water ran through the bottom of the pot (my usual measure for when to stop watering).

 

[Glaucus]

Well, that doesn't make too much sense to me. Water doesn't cause acute damage. The damage looks like frost damage, fertilizer burn, or acute drought. But you are sure they were way wetter than normally. Fertilizer burn should be quite acute, appearing in a few days or when the weather gets hotter & drier. Frost damage not a thing of course. And if it dried out, it will go limp.

Note that the damage is more on the tips and more on the new growth.

For me, overwatering causes paleness and chlorosis. If it gets root rot, then branches start to die one by one. If the root died the leaves can't get water even if the plant is watered. So that might still be a thing. But usually that will cause the entire shoot to dry out. I guess that might still happen.

 

[arctic107]

I didn't drench them yesterday, I just did two normal waterings. Maybe it wasn't enough watering even though I watered it more frequently?

 

[arctic107]

The other odd thing is that the other side of the satsuki azalea doesn't look as bad!

 

[vesper818]

It does look like fertilizer burn to me. Especially if leaves are not drooping. Maybe use just water for a while. If the damaged leaves don't completely die off, it may be ugly, but they will contribute to the health of the plant.

 

[Glaucus]

Deep Sea Diver did some underwatering vs overwatering vs overfertilizing experiments:

Thread 'Azalea-wars 2 Determining Signs of Trouble - From an inquisitive person'

Aug 21, 2022

Greetings Azalea Folks!

For years BNutter advisors have been sharing information to folks on this site about azalea issues. Specifically concerning leaf signs indicating under and over watering, sun burn and over fertilization. In this thread I decided to experiment to see just exactly what these different issues look look like.

In each trial the set up involves using two nursery satsuki azaleas. The trials were a bit tricky as it was my desire to initiate the initial signs of trouble, yet not to kill the azalea…. to be able to restore it to robust growth. This would yield...

• Deep Sea Diver
• azalea care azalea over eatering azalea over fertilizing azalea sun burn azalea under watering satsuki azalea
• Replies: 30
• Forum: Flowering

• 

I have some of my own azaleas that get discoloured grow tips that stagnate, which I suspect is from being too wet. But I have to compile some pictures of those. This affects the leaves uniformly. Not just tips.

 

[Applicative]

Where are you? this happened to mine in Dallas Texas - it hit over 100 and even in dappled shade a small window (even an hour) of direct sunlight scorches the leaves.

 

[arctic107]

Where are you? this happened to mine in Dallas Texas - it hit over 100 and even in dappled shade a small window (even an hour) of direct sunlight scorches the leaves.

I'm in Washington DC. It got into the high 80s today.

 

[Applicative]

The other odd thing is that the other side of the satsuki azalea doesn't look as bad!

Any chance if you look up where the sun is, that other side is more shaded?

 

[rockm]

I'm in Washington DC. It got into the high 80s today.

The last week or so has had very low dew points (dry, cool air) Lows in my backyard have been in the mid-50's. I've got two satsukis and when the air gets dry, they tend to dry out quickly. Since satsukis have shallow root systems and alot of roots that are near the surface, dry weather can be an issue. I use shredded yamagoke moss thinly on the soil surface, which can help.

Your problem could be drying out, could also be the soil. If you're using Kanuma, it might be a problem. The stuff breaks down VERY quickly in our climate from what I've seen. Overwatering it can be part of the problem in the summer here, as we typically have extremely humidity (DC is a reclaimed swamp after all) through the summer. I stopped using it in favor of a finer grained regular bonsai soil. That has worked better for me.

 

[arctic107]

Any chance if you look up where the sun is, that other side is more shaded?

It definitely is more shaded. The broad side of the tree faces east. The side that got burnt is towards the south. I also included a picture of my 35 year old bonsai tree which doesn't have the same problem as the younger tree.