‘seiryu’ Japanese maple forest

[b3bowen]

Probably around 5 years ago, I had the idea of making a forest planting of seiryu seedlings. My plan was to plant the forest on a rock slab. I thought the ruggedness of the stone would play well with how dainty the lace leaves are. Seedlings with small dissected leaves and good growth were selected over time. Two years ago a first iteration of the forest was placed in a 3.5 inch deep container, last year it was repotted into a 1.5 inch deep x12 x 18 inch to prepare for slab planting. It is in fine grain akadama, pumice, lava mix.

Photo from early last year.



Here is the prepared slab. It does have drainage holes drilled.


My questions are these.1. I live in 7b north carolina. Will I regret putting these on a slab. I do have automatic irrigation.

2. Should I just take entire planting, place it on slab with minimal disruption, tie down and build muck wall around it. That would leave it in akadama as above. I also purchased premade muck and it was suggested that I plant in 100% muck. Has anyone done this?

 

[19Mateo83]

Seriyu are under appreciated, they have lots of potential if you can slow them down and reduce internodes. This is a very neat idea and I look forward to seeing it all put together.

 

[RJG2]

it was suggested that I plant in 100% muck.

I don't like this idea.

 

[19Mateo83]

I don't like this idea.

Yea I don’t like this idea either.

 

[johng]

I've used straight muck for rock plantings and slab plantings for more than three decades.... Although it seems to befuddle most folks, it works very well. The trees really seem to love it. The secrets are to never let it completely dry out and to always keep a layer of green moss on the surface!!

I know, straight muck goes against what all the internet experts say about bonsai soil but you should try it before you judge it. I am at the point now that I do not even tie down my slab plantings. The muck, and later the roots, adhere well to the slab. When repotting is needed, you simply peel the planting off the slab as a single piece, remove old soil and roots from both the top and bottom of the root mass, apply a new 1\2" thick layer of muck on the slab, build up the muck on the root mass, and re-moss. This technique also works great for larger slab plantings that are heavy and difficult to move....the tree(s) can be moved separately from the slab...makes things like winter storage and two step a lot easier.

Another alternative to straight much that has also worked well for me was something I saw Ryan Neil do... He uses long fiber sphagnum moss and akadama as the soil medium. I've tried this approach twice with good to excellent results. My take of his method was to use a layer of akadama as a base and then combine long strands of sphagnum interlaced with akadama to create the walls. For this method, I used external tie down wires for the first growing season. Once everything is finished and the moss in place, wrap and connect wires over top of the soil mass and underneath the slabs. Once the roots have established in the media the wires can be permanently removed.

All that said...Seiryu, like all cut leaf varieties of maples, are not a terribly vigorous cultivar when container grown... I am not sure I would opt to put them on a slab in my climate but I am probably several degrees warmer in central South Carolina than where you are... Just yesterday, I opted to put a group of Arakawa in a container instead of a slab over the fear of keeping them watered well. It was many more trees than what you have so even that is not exactly and apples to apples comparison.

 

[RJG2]

I've used straight muck for rock plantings and slab plantings for more than three decades.... Although it seems to befuddle most folks, it works very well. The trees really seem to love it. The secrets are to never let it completely dry out and to always keep a layer of green moss on the surface!!

I know, straight muck goes against what all the internet experts say about bonsai soil but you should try it before you judge it. I am at the point now that I do not even tie down my slab plantings. The muck, and later the roots, adhere well to the slab. When repotting is needed, you simply peel the planting off the slab as a single piece, remove old soil and roots from both the top and bottom of the root mass, apply a new 1\2" thick layer of muck on the slab, build up the muck on the root mass, and re-moss. This technique also works great for larger slab plantings that are heavy and difficult to move....the tree(s) can be moved separately from the slab...makes things like winter storage and two step a lot easier.

Another alternative to straight much that has also worked well for me was something I saw Ryan Neil do... He uses long fiber sphagnum moss and akadama as the soil medium. I've tried this approach twice with good to excellent results. My take of his method was to use a layer of akadama as a base and then combine long strands of sphagnum interlaced with akadama to create the walls. For this method, I used external tie down wires for the first growing season. Once everything is finished and the moss in place, wrap and connect wires over top of the soil mass and underneath the slabs. Once the roots have established in the media the wires can be permanently removed.

All that said...Seiryu, like all cut leaf varieties of maples, are not a terribly vigorous cultivar when container grown... I am not sure I would opt to put them on a slab in my climate but I am probably several degrees warmer in central South Carolina than where you are... Just yesterday, I opted to put a group of Arakawa in a container instead of a slab over the fear of keeping them watered well. It was many more trees than what you have so even that is not exactly and apples to apples comparison.

Definitely seems counter intuitive to use something that you wouldn't think would drain/aerate well on a slab; thanks for sharing your experience!

 

[b3bowen]

Here it is all done. Will remove screens once i get moss to grow. Just used muck for my walls for now. Also, I realized my error in planting after I was done. The trees are generally flowing to the right, but the stone slants off to the left so it is as though the trees are falling uphill. I will likely flip around down the road.

 

[Shibui]

My experiences with slab plantings is not good. These dry out way quicker than a similar sized bonsai pot so be prepared to water more than a similar tree in pot. My guess is that rocks absorb water from the soil and evaporate it to the air more than stoneware fired pots. No walls also means more of the soil is exposed to dry air and hot sun. For these reasons I would not plant Japanese maples on a slab in my climate. NC is obviously a different climate so the planting may be quite OK.
These factors may be the reason that muck planting on slabs is OK. The extra drying compensates for the extra water retention of the clay soil and vice versa.
The only planting I have with similar is 3 junipers planted on an upright rock. The roots run down hollows on the rock filled with muck. The roots now follow the muck filled crevices right down to the pot below which is a shallow suiban filled with gravel so the pot fills with water every time it is watered. Being small and shallow it dries out before the end of each day so no trouble with root rot since planting around 10 years ago.

Just as pots are different from gardens so require different soil mix, slabs are different again from pots and seem to do better with another different soil mix.

 

[Cadillactaste]

Probably around 5 years ago, I had the idea of making a forest planting of seiryu seedlings. My plan was to plant the forest on a rock slab. I thought the ruggedness of the stone would play well with how dainty the lace leaves are. Seedlings with small dissected leaves and good growth were selected over time. Two years ago a first iteration of the forest was placed in a 3.5 inch deep container, last year it was repotted into a 1.5 inch deep x12 x 18 inch to prepare for slab planting. It is in fine grain akadama, pumice, lava mix.

Photo from early last year.

View attachment 470678

Here is the prepared slab. It does have drainage holes drilled.
View attachment 470677

My questions are these.1. I live in 7b north carolina. Will I regret putting these on a slab. I do have automatic irrigation.

2. Should I just take entire planting, place it on slab with minimal disruption, tie down and build muck wall around it. That would leave it in akadama as above. I also purchased premade muck and it was suggested that I plant in 100% muck. Has anyone done this?

I know a few who do small plantings on slabs in 100 % muck. My own is planted as such. eventually roots grow together...will push itself up off the slab. You prune back...slap more muck down and attach again. If I didn't trust the one who has done this process for years. I wouldn't have tried it. But I trust them...and I've not one concern about it. Why...I've clay soil for my native soil. Guess what. Trees grow in it. of course...I've never went into soil war threads. My traditional plantings are in proper Aoki for deciduous...Clay King for conifer and my Ginkgo. 100 % akadama for my Trident clump by following one I trust on that advice as well.

I actually smirked as I assembles my mini forest...knowing some would struggle with the process.

 

[Cadillactaste]

My experiences with slab plantings is not good. These dry out way quicker than a similar sized bonsai pot so be prepared to water more than a similar tree in pot. My guess is that rocks absorb water from the soil and evaporate it to the air more than stoneware fired pots. No walls also means more of the soil is exposed to dry air and hot sun. For these reasons I would not plant Japanese maples on a slab in my climate. NC is obviously a different climate so the planting may be quite OK.
These factors may be the reason that muck planting on slabs is OK. The extra drying compensates for the extra water retention of the clay soil and vice versa.
The only planting I have with similar is 3 junipers planted on an upright rock. The roots run down hollows on the rock filled with muck. The roots now follow the muck filled crevices right down to the pot below which is a shallow suiban filled with gravel so the pot fills with water every time it is watered. Being small and shallow it dries out before the end of each day so no trouble with root rot since planting around 10 years ago.

Just as pots are different from gardens so require different soil mix, slabs are different again from pots and seem to do better with another different soil mix.

I was advised to set my slab in a tray of water. Just so it can absorb water when hot...but to water regularly. I think you are onto something there. As to the guidance I was given.

 

[Cadillactaste]

Here it is all done. Will remove screens once i get moss to grow. Just used muck for my walls for now. Also, I realized my error in planting after I was done. The trees are generally flowing to the right, but the stone slants off to the left so it is as though the trees are falling uphill. I will likely flip around down the road.View attachment 475772

That's how I did this planting. Used muck to build up a wall...to plant the tree in substrate medium. It's been thriving.

Personally...if not satisfied with placement and just recently done...I would prefer setting it in order. Redoing it...than to look at it on my bench and wish I had done it later. Early on it isn't a huge issue. Roots haven't settled in and started to grow. That was advice given to me years ago. Now...if the tree was struggling before a repot. I would not mess with it. That said...this is further along...and not recently done. But...food for thought.

 

[AlexJordan]

That sounds like a beautiful project! Seiryu maples are known for their delicate foliage and stunning fall color. Planting them on a slab of rock can definitely enhance their rugged beauty.

In terms of anchoring the trees onto the slab, using wire can be a good option, especially if you drill holes into the board to thread the wire through. Another option would be to use bonsai soil mixed with a binding agent like akadama or sphagnum moss to create a layer on top of the slab, then plant the trees into this layer. The binding agent can help keep the soil in place and provide additional support for the trees as they establish themselves.

 

[b3bowen]

One thing I like about this planting is that even though all the trees leaves look almost identical by summertime, there is a lot of genetic variation visible in the early spring which to me makes it more forest like.

 

[Michael P]

Muck users, what are your recipes?

In my climate with hot dry summers I have been successful growing trident maples on slabs. My muck is bentonite clay mixed with a little organic soil and lots of long fiber sphagnum moss. The muck forms a wall at the edge of the slab with water retentive bonsai soil inside that. But I am not completely satisfied with the muck, it tends to crack and break apart when the weather is really dry.

 

[b3bowen]

Well, so far it is thriving on the slab. Heat of summer is not here yet, but I am only watering about every 2-3 days. So Im guessing once daily once it gets really hot. Just letting it grow wild for now.

 

[Shogun610]

Muck wall / mound looks alittle bigger but overall not bad I suppose overtime it will erode away to a less mounded amount
3” muck wall around perimeter then fill with base layer , secured trees the. More soil up to root flare… chop in … then gently push muck walll in to get sloped/ reinforce the muck wall .. the. Top dresss and screens

 

[Shogun610]

Muck users, what are your recipes?

In my climate with hot dry summers I have been successful growing trident maples on slabs. My muck is bentonite clay mixed with a little organic soil and lots of long fiber sphagnum moss. The muck forms a wall at the edge of the slab with water retentive bonsai soil inside that. But I am not completely satisfied with the muck, it tends to crack and break apart when the weather is really dry.

Some cracking is fine it helps form the muck wall.

 

[RJG2]

Muck users, what are your recipes?

In my climate with hot dry summers I have been successful growing trident maples on slabs. My muck is bentonite clay mixed with a little organic soil and lots of long fiber sphagnum moss. The muck forms a wall at the edge of the slab with water retentive bonsai soil inside that. But I am not completely satisfied with the muck, it tends to crack and break apart when the weather is really dry.

I'm going to give Michael Hagedorn's recipe a try:

This idea comes from Hawaii, adding corn starch as a binder. Roughly (and you can adjust proportions according to need): 1/3 small akadama plus dust, 1/3 long fibered sphagnum moss (not peat), and 1/3 corn starch. The trick is how you treat the corn starch. Before adding them together, take the corn starch and mix it in some water, then pop it in the microwave. You might have to add more water and cook it several times, but you want a jelly. Then add that to the others.
We’ve found that more corn starch than 1/3 is often needed.
It’s very pliable, and forms a dense mass once it’s dried a bit that has great penetrability when watered.

From a comment here:

Shore Pine…on a Metal Post…

For a few years I didn’t know what to do with this tree. I’d collected it with Anton Nijhuis on Vancouver Island, Canada, and remembered all too well the long, thick, stick-like root th…

crataegus.com

 

[Michael P]

Thanks! I had searched Hagedorn's site but missed this comment.