Over 2 years air-layering a juniper and still barely nothing. Does it always take this long?

[NamesakE]

I've been air-layering this juniper for about 2 1/2 years and there's barely any roots. The top is completely separated from the top and both are flourishing. What am I doing wrong?
It's probably hard to see but there's barely any roots. I put a couple more wounds on the general area but I'm not sure how much it'll help. I don't think the branch is thick enough to warrant that length of time.

 

[Paradox]

It doesnt look like you have a clean cut around the whole thing or it has bridged the cut.
If you just made small wounds hoping it would make roots from those, it wont. You have to completely separate the two areas.

Also Junipers are very hard to air layer and do not have a very high success rate if any.

 

[NamesakE]

It doesnt look like you have a clean cut around the whole thing or it has bridged the cut.
If you just made small wounds hoping it would make roots from those, it wont. You have to completely separate the two areas.

Also Junipers are very hard to air layer and do not have a very high success rate if any.

That's a bummer! I thought they air-layered easily! I checked the area and it's completely separated (you can't see from the pictures but it's completely detached and slightly swollen at the base of the cut area). There are some roots but they're small and stringy. I'm surprised the top is doing that good just from feedback from the rootstock. Guess I'll just keep waiting and hoping.

 

[NamesakE]

It doesnt look like you have a clean cut around the whole thing or it has bridged the cut.
If you just made small wounds hoping it would make roots from those, it wont. You have to completely separate the two areas.

Also Junipers are very hard to air layer and do not have a very high success rate if any.

 

[NamesakE]

What the whole plants looks like.

 

[BrightsideB]

Maybe try using a different mix for your layer. Like a pumice, bark, and spagnum mix. I’ve seen successfull juniper layers with a plastic pot as the container. Watering it everyday getting good air and water flow. And if you have roots try using some liquid organic fertilizer to help with stimulating more root growth.

 

[NamesakE]

Maybe try using a different mix for your layer. Like a pumice, bark, and spagnum mix. I’ve seen successfull juniper layers with a plastic pot as the container. Watering it everyday getting good air and water flow. And if you have roots try using some liquid organic fertilizer to help with stimulating more root growth.

It's mostly sphagnum and pumice now. But I'll definitely tend to it more. I was thinking of asking a bit of root hormone earlier myself. Glad I might be on the right track. Hopefully it'll be good by next year

 

[Shibui]

First things first.
Where in the world are you? There are definite differences in timing and effectiveness of many bonsai techniques in different climates. best to add a location on your personal profile so it shows up when you post.
The juniper looks healthy enough so vigour should not be holding roots back.
I've found junipers to root very easily but the roots do grow and develop slowly so it may take longer for the roots to thicken. Meanwhile junipers can survive with relatively few roots so maybe it is OK. Any chance there are more roots under those you can see in the pic or have you investigated thoroughly?
Junipers do not like roots too wet. It is possible your sphagnum/ pumice mix is just a bit too wet for the roots to grow well.

I checked the area and it's completely separated (you can't see from the pictures but it's completely detached and slightly swollen at the base of the cut area).

If the layer is completely detached then how/why is it still on top of the tree. Maybe detached means different thing to both of us?

 

[SeanS]

Your first photo shows a bunch of missing bark/wounds to the branch just above where you’re trying to layer. Why is that? Have you just made some haphazard wounds to the bark in that area to try to generate roots?

 

[NamesakE]

First things first.
Where in the world are you? There are definite differences in timing and effectiveness of many bonsai techniques in different climates. best to add a location on your personal profile so it shows up when you post.
The juniper looks healthy enough so vigour should not be holding roots back.
I've found junipers to root very easily but the roots do grow and develop slowly so it may take longer for the roots to thicken. Meanwhile junipers can survive with relatively few roots so maybe it is OK. Any chance there are more roots under those you can see in the pic or have you investigated thoroughly?
Junipers do not like roots too wet. It is possible your sphagnum/ pumice mix is just a bit too wet for the roots to grow well.

If the layer is completely detached then how/why is it still on top of the tree. Maybe detached means different thing to both of us?

Sorry, should've been a bit more clear. I meant detached as in there's only phloem/hardwood keeping it connected to the rootstock. All the outer tissue (xylem, cambium, bark) on the upper piece is detached from the outer tissue on the rootstock. As for location I'm in the northern U.S. Michigan to be precise.

 

[NamesakE]

Your first photo shows a bunch of missing bark/wounds to the branch just above where you’re trying to layer. Why is that? Have you just made some haphazard wounds to the bark in that area to try to generate roots?

Yeah I added a few extra wounds hoping their exposer to the soil might help get things going a little more. A hail a Mary move I'm sure. : )

 

[Shibui]

If the cambium is disconnected from trunk below that's as good as you can get. Adding new wounds will not make any difference IMHO.
There's 2 strategies I would try:
1. use better soil mix for the layer. I suspect the current mix is too wet for good root growth but very hard to be sure from this distance.
2. take the layer off with just a few roots. I'm regularly amazed at how few roots layers need to stay alive after separation. Separation also seems to give the tree a wake up call and they soon have lots of roots after being removed from the stock plant.

 

[NamesakE]

If the cambium is disconnected from trunk below that's as good as you can get. Adding new wounds will not make any difference IMHO.
There's 2 strategies I would try:
1. use better soil mix for the layer. I suspect the current mix is too wet for good root growth but very hard to be sure from this distance.
2. take the layer off with just a few roots. I'm regularly amazed at how few roots layers need to stay alive after separation. Separation also seems to give the tree a wake up call and they soon have lots of roots after being removed from the stock plant.

Thanks for the advice! That's the hard part about this hobby. Putting years into something with a unknown chance it could die.

 

[snowman04]

I always look at it as the journey... Your project will get where it needs to be.

 

[Mike B]

Thanks for the advice! That's the hard part about this hobby. Putting years into something with a unknown chance it could die.

well it is 2 years later, what do the roots look like now ?

 

[Bonsai Nut]

I'm not sure what I'm looking at - there appears to be soil at the location of the air-layer(?) Did you see my resource on air-layering?

Thread 'The science of air-layering'

Apr 2, 2017

Because of the number of questions regarding air-layering on the site, I have attempted to pull together an overview of the science behind air-layering which will directly lead to a list of "best practices" and "frequently asked questions". I am going to try to keep the science really simple (because it gets extremely complicated very quickly) while at the same time ensure that everything I write is scientifically grounded.

Introduction
Air-layering as a way of propagating bonsai material that has some unique advantages. First, the material being layered is a genetic clone...

• Bonsai Nut
• Replies: 231
• Forum: Grafting, layering & propagating

• 
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[ralfish]

Ive air layered a fair number of index finger thick junipers in recent years and there are some instances where it goes quite quickly. i think it would also vary by species and cultivar though. Looking at the stem you want to layer off, if it has undeveloped adventitious buds, it will root quickly at that point. They look like small bumps. Sometimes a hard pruning will stimulate them to form. They can turn into branches also, but if you see them, its a good place to do an air layer. Takes a couple of months. Even if not a lot of roots form while still attached, so long as there is change in those buds. I've removed branches this way that hardly had any root growth but the buds had all started growing but some were just swelling up. 2 months after cutting off they had lots of fully developed roots. When I've done layers where there were no adventitious buds showing, it took upwards of 2 years(this parent tree was in the ground in the shade). Its useful to prepare the tree ahead of time as much as possible too. Start fertilising heavily in the spring. I sometimes apply a wire tourniquet about 3mm above the top end of the cut. In your case, maybe very carefully examine it to see if it is calousing over instead of growing roots. If its callusing re-scrape the cut and repack with chopped up dampened sphagnum. If you have any rooting hormone brush it on before adding the moss.

 

[SeanS]

Ive air layered a fair number of index finger thick junipers in recent years and there are some instances where it goes quite quickly. i think it would also vary by species and cultivar though. Looking at the stem you want to layer off, if it has undeveloped adventitious buds, it will root quickly at that point. They look like small bumps. Sometimes a hard pruning will stimulate them to form. They can turn into branches also, but if you see them, its a good place to do an air layer. Takes a couple of months. Even if not a lot of roots form while still attached, so long as there is change in those buds. I've removed branches this way that hardly had any root growth but the buds had all started growing but some were just swelling up. 2 months after cutting off they had lots of fully developed roots. When I've done layers where there were no adventitious buds showing, it took upwards of 2 years(this parent tree was in the ground in the shade). Its useful to prepare the tree ahead of time as much as possible too. Start fertilising heavily in the spring. I sometimes apply a wire tourniquet about 3mm above the top end of the cut. In your case, maybe very carefully examine it to see if it is calousing over instead of growing roots. If its callusing re-scrape the cut and repack with chopped up dampened sphagnum. If you have any rooting hormone brush it on before adding the moss.

I second the point of the “small bumps”
I’ve had those small bumps on juniper trunks literally develop aerial roots if the area where they are is close enough to the soil line to stay mildly moist.