Satsuki Azalea Bonsai - brown spots

[bonsaibeginner123]

This is my first bonsai and received it as a gift over a month ago. I am located in california. The bonsai is outside and I water it whenever the soil is dry (twice in a day attimes). From last couple of weeks, the air quality was "moderate" due to wildfires. So, I had it indoors for couple of days last week. And I probably missed one day of watering earlier this week (or watered late in the day). Now, the leaves have brown spots for couple of days now. I am worried it is dying. Hope the attached pictures help. Please let me know how to revive it.

 

[bonsaibeginner123]

just to add to it - USDA Zone 9 - San Jose ,CA

 

[Deep Sea Diver]

Could be one of four things…….

1. Too much sun, especially in the heat of the day. I know folks with azaleas in your neck of the woods that use at least 50% shade cloth all day.

2. Overwatering…. Azaleas like soil that is moist, not wet.

3. Too much fertilizer… esp in summer… many cut back during hot days

4. Underwatering…. Most folks don’t do this, but it’s often coupled with limp. softening* foliage

If it were here, I’d go with 1 or 3. Over fertilizing is the number one killer of azaleas…. followed closely by overwatering…. but lately we are seeing a lot of sunburn on our azaleas, well, the temps did get to 110F here. This is what one of our hardiest azaleas looked like 2 weeks later… it was covered by netting…! … and an uncovered one a month later.

covered


uncovered



overfertilized after recovering… accidents happen! If this is the reason you can try to flush the extra ferts out, only if you have a excellently draining soil like kanuma - which when intact can’t hardly be overwatered…. But beware of doing 5his with peat based soils, you migh5 switch one problem for another even worse, root rot.

cheers
DSD sends

You can see these two issues look eerily similar…

cheers
DSD sends

 

[bonsaibeginner123]

Thank you so much for your prompt reply. I appreciate your detailed diagnosis.

1. That is a great point. It is probably too much sun. I have couple of other plants with some brown leaves too. I have a small balcony, I will try using something like this (attached picture). Is it okay to move it in shade temporarily before I get a shade cloth?

3. The store that shipped me this bonsai had some fertilizer added to the soil. When I called them regarding adding fertilizer, they said it is good for the rest of the year and I don't have to add until next spring. So, I haven't added any fertilizer since I received the plant in mid July. Do you think I need to fertilize it? I bought superfly bonsai fertilizer 5-7-4 but haven't used it. Is there a different one you recommend?

 

[Paradox]

It looks like it could be a fungus to me but that would be odd if your climate is dry and not humid. It's possible the air quality might be effecting it too.

I've started using fertilizer for acid loving plants on my azaleas because they are acid loving.

My azaleas get morning sun and afternoon shade. If you can move it to a more shady area, I would do that.

 

[Deep Sea Diver]

That depends… the folks who sold it said it was fertilized. That might mean a nursery blend soil which is easily overfertilized.

What type of media is your azalea planted in?

Cheers
DSD sends

 

[Deep Sea Diver]

Can you please enter where you are located? Located in California could be any of many USDA zones. Please double click on your icon and entered your approximate loca and USDA zone. This will help everyone that you chat with.

Once this information is entered we can give you more specifics on things like shade cloth etc. At this point I’m not sure if your issue is sun, but it’s likely from your input. Once we know the type of media and approximate location your situation will be more clear.

cheers
DSD sends

 

[bonsaibeginner123]

I entered my location and USDA zone. Thanks for letting me know. Regarding the soil, I don't know what soil it is. I called Brussels Bonsai which is where I received this plant from and they said they use their own soil mixture. I am not sure if a picture of the soil will help. Thank you for all the advice.

 

[Deep Sea Diver]

Based upon what I can see, I’d say their is a good deal of fertilizer and looks really wet besides the probable sun issue.

My thoughts…
….knock off at least half of the slow release fertilizer and be very circumspect with watering along with get some good shade cloth.

Azaleas shut down when the temps get above 90 degrees so the plants aren’t going to take up much water….

Misting the leaves often vs watering when it’s hot….less when it’s not would be very helpful. Be sure the leaves are dry before misting again and avoid misting at night if the leaves will not dry.

Cheers
DSD sends

 

[Clicio]

I entered my location and USDA zone. Thanks for letting me know. Regarding the soil, I don't know what soil it is. I called Brussels Bonsai which is where I received this plant from and they said they use their own soil mixture. I am not sure if a picture of the soil will help. Thank you for all the advice.

I agree with DSD, looks way too wet this soil.
Here in the tropics, azaleas will be sent do dappled shade from mid Spring to mid fall.

 

[bunjin]

Well, If it were my azalea I would repot right away, but maybe it would be best for you to do some research first. Fresh soil normally results in better moisture control. I would also see what help the Bay Area Satsuki Aikokai club may be able to offer. On Oct. 2-3 there is a GS Bonsai Federation event near you in the metropolis of Santa Nella. Info is posted on the aforementioned club page. It would be a good opportunity to pick up media materials as vendors will be there. The Superfly fertilizer seems like it would be good as it is an organic product and is naturally a slow release. I would avoid chemical fertilizers, osmocote and derivatives as azaleas are not heavy feeders and one is likely to do more damage than good. Good luck with it.

 

[Maiden69]

I just received an Elm from them and that soil was muck! It looked too wet and when dried up didn't let any water in. I bare rooted and repotted into inorganic soil about a little over a week ago, I didn't cut back unless it was necessary. The tree is already throwing new green shoots now. I don't know how they expect people that have never dealt with trees let alone bonsai, to keep this trees alive. I think from the few nurseries I have order trees, their soil is the worst.

Proposal: CE Mallsai / Cheap as chips Contest

Here is a link to the $27 one on Amazon. If you notice, they also have a medium size. Hope this helps: Small Chinese Elm for Sale. Yes, I bought the medium one. What I meant was a place where I can go see them and pick the one I like, not a mail order where they just grab a box and the next...

www.bonsainut.com

I knew it was Brussels when I saw the gravel (I think its big DE) and the thick aluminum wire.

 

[Maiden69]

Azaleas shut down when the temps get above 90 degrees so the plants aren’t going to take up much water….

Well, I guess they shut down unless you prune them a bit too hard. The one I pruned a few weeks ago that was kinda chlorotic is throwing shoots everywhere. I seriously think I should bare root next year out of the nursery potting soil and plant in kanuma.

 

[Deep Sea Diver]

Well, I guess they shut down unless you prune them a bit too hard. The one I pruned a few weeks ago that was kinda chlorotic is throwing shoots everywhere. I seriously think I should bare root next year out of the nursery potting soil and plant in kanuma.

Concur…. I find kanuma to be a good media myself. Others think differently. Actually I use 90/10 Kanuma/pumice and it responds well to both hot and cold temperatures. It is really hard to over water. One would have to really work at it. Some cooler days I can skip watering and just mist…. Which I usually do 1 - 2x a day anyways, depending on the high temperature. The northern, narrow leaved azaleas don’t like the heat at all and respond really well to misting.

I did a little research on Brussel’s Bonsai soil. Here’s their blurb:

After receiving your tree, wait at least one growing season before repotting. Using proper bonsai soil is critical. Brussel’s bonsai soil consists of a mixture of high-fired clay particles and finely ground pine bark. The soil-free mix does not compact, allows water to drain easily, plus helps prevent the root rot.

imho This wouldn’t be my first choice of all the media’s I’ve seen used. Also explains a lot about why you are having issues. So be careful to only water when you need to. You can add 1 tsp 3% Hydrogen Peroxide to 16oz water to help prevent root rot every other week to prevent root rot. btw @Maiden69‘s experiences are right in line with what is being seen. Using bark is not uncommon, but ground up bark seems unusual. Check out this survey from last year about media types….

Yep . We had two heat spells out here the Big Heat Dome (for us) where it hit 110F…. except at night.where temps were briefly in the high 70’s and the Little heat where it topped off at a balmy 96F. Nothing was moving on either spell, but a week later as temps dropped in the high 70’s the trees really moved in Azalea Land. (My back yard with over 70 various sized 1-6 yoa azaleas). They haven’t stopped growing since.

cheers
DSD sends

 

[Maiden69]

Actually I use 90/10 Kanuma/pumice

That is what Peter Warren recommends as well. It is what he used for an azalea repot in a Mirai stream.

After receiving your tree, wait at least one growing season before repotting. Using proper bonsai soil is critical. Brussel’s bonsai soil consists of a mixture of high-fired clay particles and finely ground pine bark. The soil-free mix does not compact, allows water to drain easily, plus helps prevent the root rot.

Yeah... that bolded quote does not describe their mix, unless it is like that when they plant the tree and it completely degrades and compacts within a few months. I usually save the potting soil I get from nurseries for a "just in case", I used Brussels to fill a low spot in my bermuda grass next to a sprinkler valve box.

 

[Carol 83]

I think from the few nurseries I have order trees, their soil is the worst.

I have to agree. Not saying the trees aren't healthy, they obviously couldn't be the bonsai giant selling an inferior product, but...

It looked too wet and when dried up didn't let any water in.

Same here, dried up and was almost impossible to water.

 

[Deep Sea Diver]

Makes sense as pulverized pine bark would act like peat when dries hydrophobic for sure.

I did get that idea from Peter Warren sometime last year…. after testing Kanuma/Chopped Sphagnum 80/20 in last years trees. So I ran a test. At this point I’m not sure which is better. Possibly the Kanauma/Sphagnum by a neck, yet it’s hard to compare year groups as these are each in different states of development. But both work well.

That said, I’d repot that mess for sure late next February if I was the OP.… @bonsaibeginner123 .

cheers
DSD sends

 

[Maiden69]

I did get that idea from Peter Warren sometime last year…. after testing Kanuma/Chopped Sphagnum 80/20 in last years trees. So I ran a test. At this point I’m not sure which is better. Possibly the Kanauma/Sphagnum by a neck, yet it’s hard to compare year groups as these are each in different states of development. But both work well.


cheers
DSD sends

His reasoning was that he likes to use 5-10% pumice because it will allow to hold structure in the soil because kanuma breaks down rather quickly. I don't know how much 10% of pumice will improve the structure of the soil, but I'm sure he wouldn't use it if he had seen any draw back to it.

 

[Deep Sea Diver]

Yep, it’s a very slight amount and doesn‘t seem to make any difference in holding water. Maybe it would down south, where Gondo’s folks used to profess adding sphagnum. As you said, it’s a very slight amount.

The pumice would affect the Cation Exchange Capacity and water holding attributes of the media slightly, yet since Kanuma is so high in both of these areas, its not noticeable.

I can put a pot of the Kanuma/Sphagnum mix right next to a pot of the Kanuma/Pumice mix and they both seem to dry and rewet similarly.

It does “work” slightly better…. yet looking at it from a critical perspective, it almost seems to me that this was a cost saving move.

cheers
DSD sends