Deciduous Azalea Techniques

[NorthernLightsBonsai]

Hello @Leo in N E Illinois and all,
This thread is the reason I joined this forum, good and interesting stuff here! Let's keep it going!! I was primarily interested in Minnesota Native Yamadori (Cedars and Larch), but with these Deciduous Northern Lights Azaleas coming from my Alma Mater, I'll consider them Native-Adjacent. I've scoured the local garden centers in my area and am starting with three of the Northern Lights (Northern Hi-Lights, Electric Lights Red, and Candy Lights), selected for their trunks, leaf size, and visual node/growth characteristics relative to some of the other Northern Lights Azaleas. I'm particularly hopeful for the Electric Lights Red, as it seems to be relatively more compact and have smaller leaves than all the others I looked at. So from here I'm seeking general guidance on how to proceed as I'd like to progress this thread and be a regular contributor.

As of right now (June 8th, 2024 in the Twin Cities [4b]) My plans for the very near future are to do a drastic cut-back and repot all the plants into some custom wood grow boxes with 100% Kanuman and if I can find any maybe some top dressed Sphagnum. Stop me there if you advise against any of this.

Assuming I'm safe to move forward with my intentions here are the general questions I have:

-What percent of the root mass do you all feel is safe to remove?

-Cut-Paste? If so, does anyone have a recommended brand/product they have had great results with?

-Anything else?

Thanks to all in advance, I'll follow up with before and after pictures based on the actions I take from the advice given.

-Casey

 

[Deep Sea Diver]

Hello @Leo in N E Illinois and all,
This thread is the reason I joined this forum, good and interesting stuff here! Let's keep it going!! I was primarily interested in Minnesota Native Yamadori (Cedars and Larch), but with these Deciduous Northern Lights Azaleas coming from my Alma Mater, I'll consider them Native-Adjacent. I've scoured the local garden centers in my area and am starting with three of the Northern Lights (Northern Hi-Lights, Electric Lights Red, and Candy Lights), selected for their trunks, leaf size, and visual node/growth characteristics relative to some of the other Northern Lights Azaleas. I'm particularly hopeful for the Electric Lights Red, as it seems to be relatively more compact and have smaller leaves than all the others I looked at. So from here I'm seeking general guidance on how to proceed as I'd like to progress this thread and be a regular contributor.

As of right now (June 8th, 2024 in the Twin Cities [4b]) My plans for the very near future are to do a drastic cut-back and repot all the plants into some custom wood grow boxes with 100% Kanuman and if I can find any maybe some top dressed Sphagnum. Stop me there if you advise against any of this.

Don’t do much deciduous azalea, but best thing to do imho is to cutback to inner green foliage if possible. Yet if there are a number of azaleas on hand, would suggest experimenting, some cut back to green others cutback hard and guage the results in your area.

Assuming I'm safe to move forward with my intentions here are the general questions I have:

-What percent of the root mass do you all feel is safe to remove?

See what is recommended in the thread. If you can’t find any specifics, wouldn’t go more that 50%

That said, would not change the media at the same year as you cut back hard…. At least for your first year trials. That’s too much damage at one time and will obscure the cutback results.

-Cut-Paste? If so, does anyone have a recommended brand/product they have had great results with?

Top Jin cut paste works well on all azaleas. Would consider for larger stubs to use the green topped cut putty on top of the Too Jin once the Top Jin is hardened off .

-Anything else?

Whatever is done, be systematic and document the steps you took for each tree. It’s the best way to ensure success next time.

Thanks to all in advance, I'll follow up with before and after pictures based on the actions I take from the advice given.

You are welcome!

Best of luck and am looking forward to seeing your future results.

Cheers
DSD sends

 

[NorthernLightsBonsai]

Here we go,
As mentioned before I’ve started with three nursery stock 3 gallon Northern Lights Azalea plants (Northern Hi-Lights, Candy Lights, and Electric Lights Red). The plants were selected from the available options I was able to find for their respective trunk, leave size, and node length/growth characteristics.


Quick note, of the three I’m most optimistic for the Electric Lights Red Azalea. I’m hopeful that it’s smaller leaf size and more compact growth characteristics lend itself to bonsai.


Wednesday night (6/12), I repotted all three plants into 9”x11”x6” grow/training boxes filled with Kanuma and top dressed with Yamagoke (Mountain Moss). For the repotting process, I pretty much bare-rooted all three plants, though I’ll note that I didn’t do as good of a job of breaking up the central root mass on the Northern Hi-Lights, which I repotted first, compared to the following two plants.

That same night, all three plants were also given a hard prune. The Electric Lights Red and the Northern Hi-Lights were cut all the way back to what I considered their “good structure” portions of their primary branches, with all leaves, shoots, and secondary branches removed. The Candy Lights was given a less aggressive hard prune, with about 50% of its total foliage removed, including most branches that didn’t lend to good structure. Given the structure of the trunk I couldn’t decide which branch I liked better as the “leader”, also keeping Deep Sea Diver’s cautionary advice in mind, I opted to leave two branches as potential “sacrifice branches”, to see how the Azalea responds, and in the hopes of seeing if I can thicken up the trunk and branches.


All cuts were treated immediately with Top Jin M and then the next day, after the drying/curing, the cuts were covered with (gray) Cute Paste Hi.

Presently all plants have been well watered and resting in my garage. They’ll hang out there for a couple of days and then in the near future be relocated to my garden area once I get some shade cloth figured out.

The goal from here is to not kill any of the plants, if I haven’t already, and hope to facilitate a state of recovery, root growth, and hope the plants bud out.

 

[Tak]

Also following this post

Just picked up a Northern lights and a Girard's pleasant white.

They seem to be doing well but are pretty root bound and I want to split at least one that has two plants in the same container.

It's now Aug 7th in south central Ontario (5a) and I am wondering if I can split/transplant in bigger pot at this time.

I want to let them grow but I also don't want them to keep stretching so not sure if I should do a slight prune or let them go and do a harder prune next year.

Some amazing info on this thread but I am overloaded

Would for sure like to split/repot them in bigger pots asap so they can get growing but wondering if it is too late.

 

[NorthernLightsBonsai]

@Tak ,
Good to hear from you, happy to bounce things off someone doing the same thing. I've been meaning to post an update but figured I'd wait until I hit the 60 day mark on my projects...
To respond to your question, I'm by no means no expert, just some googling and I've read all the posts on this string and a couple others, but my primary advice is to proceed with caution.
We're pretty late in the growing season, so the main focus, as I understand it, is to not stress these plants out too much because the summers are still hot. Repotting is probably the most stressful event we'll put these plants through, followed by major chops/prunes. Not sure what your growing situation is in terms where they are located and how controlled their environment is (outside vs. greenhouse), but it's kind of a fine balancing act providing the plant the proper environment to recover from the stress, without gettting overstressed by the growing environment, while allowing it to take in the necessary nutrients to survive, while not disrupting the fine equilibrium of leaves to bring in sun and roots to bring in water/nutrients to the point that the plant dies.
All that to say, you might be able to get away with a repot and gentle prune, but I wouldn't do anything too drastic, and be prepared to give the plant some extra TLC so that it can recover and get ready for winter.
My plants are under 40% shade cloth and seem to like it, but also with that said I did lose one, probably because I stressed the plant too much with the repotting+massive chop. I likely removed too many roots too late in the season, so even though it did push a bunch of backbuds out that grew to small leaves, I suspect the roots couldn't keep up with the demands of the leaf growth with all the stress of trying to recover so that particular plant was in a slow state of decline despite looking like it was doing alright.

Keep me/us posted!

 

[Underdog]

I would suggest you pull it out of the pot and lightly tease the outer roots and put it in a grow bed/ground until spring. That young of a plant could probably take it but...

Were it me I'd probably (rip them apart) separate them and put in the bed until spring. or a few years even.

 

[Tak]

I would suggest you pull it out of the pot and lightly tease the outer roots and put it in a grow bed/ground until spring. That young of a plant could probably take it but...

Were it me I'd probably (rip them apart) separate them and put in the bed until spring. or a few years even.

I think #2 might be my play. Looks like we may be entering that third window for repotting that Leo was talking about as the nights are starting to cool.

 

[Tak]

@Tak ,
Good to hear from you, happy to bounce things off someone doing the same thing. I've been meaning to post an update but figured I'd wait until I hit the 60 day mark on my projects...
To respond to your question, I'm by no means no expert, just some googling and I've read all the posts on this string and a couple others, but my primary advice is to proceed with caution.
We're pretty late in the growing season, so the main focus, as I understand it, is to not stress these plants out too much because the summers are still hot. Repotting is probably the most stressful event we'll put these plants through, followed by major chops/prunes. Not sure what your growing situation is in terms where they are located and how controlled their environment is (outside vs. greenhouse), but it's kind of a fine balancing act providing the plant the proper environment to recover from the stress, without gettting overstressed by the growing environment, while allowing it to take in the necessary nutrients to survive, while not disrupting the fine equilibrium of leaves to bring in sun and roots to bring in water/nutrients to the point that the plant dies.
All that to say, you might be able to get away with a repot and gentle prune, but I wouldn't do anything too drastic, and be prepared to give the plant some extra TLC so that it can recover and get ready for winter.
My plants are under 40% shade cloth and seem to like it, but also with that said I did lose one, probably because I stressed the plant too much with the repotting+massive chop. I likely removed too many roots too late in the season, so even though it did push a bunch of backbuds out that grew to small leaves, I suspect the roots couldn't keep up with the demands of the leaf growth with all the stress of trying to recover so that particular plant was in a slow state of decline despite looking like it was doing alright.

Keep me/us posted!

Thanks for the update! Yeah you sure put them to the test. Glad to hear two survived, they will make fin trees. I will likely just separate and repot in bigger grow bags. And try to insulate the pots with leaves this winter.

 

[Deep Sea Diver]

Hmm… we do lots of work on evergreen azalea, little on deciduous, however our experience with azaleas this close together, it is more successful to do this operation in late winter early spring. There is little to be gained by splitting now and higher risk.

Not saying one shouldn’t, just providing data.

Good Luck
DSD sends

 

[Tak]

Hmm… we do lots of work on evergreen azalea, little on deciduous, however our experience with azaleas this close together, it is more successful to do this operation in late winter early spring. There is little to be gained by splitting now and higher risk.

Not saying one shouldn’t, just providing data.

Good Luck
DSD sends

Thanks DSD.

I had already proceeded but was extra careful. Was able to split one with minimal work, the other one I slip potted. They don't see to have noticed. Now the conundrum will be how to overwinter them in zone 5-6.

Thinking I will put them in my cold cellar but wondering if they will need light during dormancy.

Planning ahead I know

Here they are

 

[Deep Sea Diver]

Glad it was easy to do. We’ve had some bad experiences trying to aerate azaleas.

Wintering over. Being deciduous likely they would be fine in a cold cellar. Most want to keep a small fan running to avoid fungus issues.

Once buds start to push the tree may need an intermediate spot, like a mud room with a window and a heater if it gets below freezing.

Good luck
DSD sends

 

[Underdog]

Northern Lights:
This is a hardy series of azalea hybrids (Rhododendron) which were developed in Minnesota for bud hardiness. They can withstand temperatures as low as -35° F without significant damage. Azaleas are deciduous (drop their leaves in fall), and have five stamens in each flower.

In my opinion you should mulch it in outside. More chance of killing w/kindness inside. Set it and forget it after a couple frosts.

Girards is not deciduous but good to zone 5. I have some.

You should start a thread of your own on these and check in here w/updates and lessons learned.

 

[NorthernLightsBonsai]

****71 Days Later - Update****
After a bit over two months with my Northern Lights Azaleas I figured now is a good time to check in. For the last two months my plants have been in 100% Kanuma filled training boxes, under 40% shade cloth, in a spot on my yard that gets mostly direct sun. I water them pretty much every other day, weather depending, have just started fertilizing using a 30-10-10 fertilizer, and also have been treating my bonsai projects with some of the fishtank water from my son's aquarium as I do water changes.

-The Electric Lights Red (The Bad): This plant budded out slower than my Northern Hi-Lights, got to a point where there were a bunch of small leaves all over, and then withered and died despite getting the same care as the other two. I suspect I stressed the plant too much with the mid-June repot and hard prune, so while the plant had energy to bud out and grow leaves, I believe it was essentially doomed and just going through the motions as it died off. Sad to see it go because while the structure of the trunk wasn't the best, I did like the smaller leaf size compared to the other two for bonsai purposes.

-Candy Lights (The "OK"): I took a more experimental approach to this plant as I wanted to thicken the trunk structure and see how it would back bud with only a medium-light prune. So I only chopped the portions of the trunk and foliage that didn't lend to good bonsai structure and look at all the remaining foliage as "sacrifice branches" for next year when I form a better idea of where to go with this plant. Overall, I'd say the plant is healthy and adapting to the training box, with what I presume to be next year's flowers developing on the ends of most of the branches. Interestingly, despite about 50% of the total foliage being removed, I only see backbudding and new growth on the portions of the trunk and limbs that got chopped. Likely major hard pruning planned for next season now that the roots seem to have established...


-Northern Hi-Lights (The Good): What started out as a hobby "love letter" to my wife, because she wanted a white flowering azalea, has quickly become the pride and joy of my original three plants. Despite having larger leaves than the Candy and Electric Reds, the trunk/branch structure of this plant was easily the best in terms of bonsai appeal. After the hard prune the plant back budded hard and the leaves grew back vigorously. Also interesting to point out, the new growth didn't shoot up so much, like the original structure of the plant pre-chop. The leaves/nodes are much more compact/tight to the original trunk. Ramification?? We'll see after next Spring... but for now I'm extremely happy and optimistic for the future of this plant.


Moving forward I don't necessarily foresee any major pruning or wiring for my azaleas this year, likely just some structural maintenance pruning to remove shoots popping up where I don't want them.

I'll check back in later this Fall once I figure out my winter storage situation or if anything major happens.

To Tak and all others doing the same, keep me/us posted! I'd like to know what your fall intentions/happenings look like.