Hinoki Trouble

[Kodama]

Hey BNuts! Having trouble with this Hinoki. As you can see quite a few tips are turning brown throughout. I think it might be roots getting too hot. The pot absorbs alot of heat. I do keep it well watered so maybe I'm overwatering just a bit. I do have it under 40% shade cloth mid day so I don't think it's from direct sun scorch. It's been progressive as the summer heat kick up so wondering how tolerant they are. Thoughts and suggestions welcome.

 

[Kanorin]

Hey BNuts! Having trouble with this Hinoki. As you can see quite a few tips are turning brown throughout. I think it might be roots getting too hot. The pot absorbs alot of heat. I do keep it well watered so maybe I'm overwatering just a bit. I do have it under 40% shade cloth mid day so I don't think it's from direct sun scorch. It's been progressive as the summer heat kick up so wondering how tolerant they are. Thoughts and suggestions welcome.

40% shade cloth is great, that's what I have mine under as well. It's fairly normal for interior or shaded out foliage to be shed by Hinoki - the amount you have going on seems a bit on the high side, though. What else have you done to the tree this year? Any repots, wiring, or cutbacks? Sometimes they will show this response a month or two after you do a big wiring or repot, for example.

In the mean time, cover the pot with an old cloth, undershirt, or aluminum foil. And pull off that brown dead foliage with your fingers - it should easily pluck away. This will increase air flow and light to the remaining foliage.

 

[River's Edge]

If possible a side photo showing the base of the tree and the pot. It appears that a lot of roots are exposed and possibly the tree is potted too high up in the pot. Hinoki are also sensitive to root disturbance and repotting should be done more carefully than most species. I concur that it would be helpful to know more about the length of time since repotting and a visual for better understanding of the situation.

 

[Kodama]

I did a repot in early spring but very little root trimming and 1/2 bonsai soil. APL 1:1:1.
I thought it recovered quite well but as the summer progresses I see it more and more. I'll cover the pot with a white cloth to hopefully cool it down. Thank you for that suggestion.

 

[River's Edge]

I did a repot in early spring but very little root trimming and 1/2 bonsai soil. APL 1:1:1.

So 1/2 is the remaining compacted soil? Is that correct?

 

[penumbra]

Hinoki cypress are rather like the primadonna of conifers. My personal experience when growing as a bonsai, is to mess with them as little as possible, protect them from afternoon sun, and never let the go completely dry. I grow mine in a loose mix with plenty of organics and in dappled sun under larger trees. I work on them as little as possible, very judicious in my pruning and re-potting no more than every 4 - 5 years. Often I go longer. I rather let the plant do its own bonsai thing with just a hint of human activity here and there. This refers to the compact forms.

 

[Kodama]

The remaining is soil is a bark soil compost and is very free draining. Here is a side photo. You think it's potted up too high above the pot? I placed moss in the spring to help cover and protect. I'm clearly doing something wrong. 5 years in and I'm still so much a noob. Could it be too much moisture and the new root tips are getting cooked?

 

[Hartinez]

I actually think your tree is going to be just fine. It’s possible the tip death is still a lingering response to the repot. Other than the handful of brown tips, the tree is a vibrant green with tons of growth at the tips. If it were mine, I’d continue to remove all brown tips favoring the healthy ones and keep it moist but not soaked, which should be easy considering the free draining soil. It is potted too high which you will want to address at some point. Def not full sun, but this tree should also not be in mostly shade. These are all my thoughts on my own Hinoki experience, which can vary from location to location. So take all my advice as someone growing Hinoki in zone 7b high desert New Mexico.

 

[stubmle]

I also have a struggling Hinoki... though in my case I am sure I was too rough with the roots this Spring. It was badly pot-bound in nursery soil and I had to really hack at the roots, they were so dense. It looks similar to OP's now, but worse. I suspect it's not going to survive the Winter, but I'm not giving up until it's totally toast. Just praying, watering heavily, and keeping in dappled shade for now.

Another Hinoki I have that I was much gentler with and planted in a more moisture-retentive mixture is doing fine, even in full sun. They seem to like lots of water, even on the foliage. I hose down the whole plant daily and it couldn't be happier from what I can tell- lots of thick, vigorous growth all over.

I agree with Frank, they do not respond well to heavy root pruning or dry conditions. I think going forward I am going to incorporate more organic material in their soil mix, they seem to appreciate it. As long as they're not sitting in water all day (be mindful of perched water tables), I don't know that it's possible to overwater a Hinoki, especially in a primarily-inorganic substrate. I have seen it mentioned in other threads on this forum that one reason they are not very popular trees in Japan because they need much more watering than most other conifers do.

These trees love to drop older, interior foliage and back-budding is as rare as hens' teeth. In my experience, normal die-back usually occurs over Winter and is evident in Spring or early Summer. However, browning of exterior foliage typically indicates a problem- usually sun scorch or exposure to excessively dry wind that kills the foliage outright. If neither of these are likely, then it may be a stress response to sickness or injury. I think Mr. Hartinez is correct in that it's a delayed reaction to the repotting, hopefully not a total decline due to some other issue. The tree does have lots of healthy growth still, which is a good sign.

I'll cover the pot with a white cloth to hopefully cool it down.

I think that is a good idea. Next Spring, if the tree is healthy enough, you might be able to either move it to a deeper pot or lower in the same pot. In the meantime you could also consider top-dressing with chopped sphagnum moss to help keep the roots cool and moist. As it is they are very exposed and may be drying out too much.

Out of curiosity, do you know what cultivar this is, if any?

 

[Deep Sea Diver]

Not too sure about the root pruning, although it could be a contributing factor. At first seems somewhat mystifying as there is a good deal of living growth mixed in with the dead tips. Worked on a couple trees at Elandan gardens similar issue, but worse. Believe Dan said the tree was ‘too dry’ and too much sun.

Also have one in the yard given to me last that had similar damage as a layover the heat dome.

Damage is differential throughout the tree, often more in the interior. Looking at the Hinoki in the images the tree looks likes it has lost lots 9f interior foliage over time.

There was one issue for all the above trees.

Core of media was too dry. In Dan’s case, all the media was too compacted. My solution my solution was to drill the root ball right off annd allow penetration of water. Then repotted the next spring, removed much of the core, reduced the roots as indicated. Drilled the remainder. Goal get similar water penetration as new media.

Wrote a thread about this tree here.

Cheers
DSD sends

 

[Kodama]

Out of curiosity, do you know what cultivar this is, if any?

Unfortunately I am not sure exactly. I picked it up as pre bonsai material 2 years ago at Chicago show and should have asked.

 

[Kodama]

Thank you all for taking the time to offer your advice and feedback. Very much appreciated!

 

[Deep Sea Diver]

There isa reason why these issues show up in the summer after a report. That’s when the tree is most stressed.

In this case it would be best to keep the tree in part shade even after the core is drilled.

We use 3/16” bit. Flag the bit with tape at just less then the inside depth of the plot so the drill will not contact the plot bottom. Let the drill find its way through the media. It will avoid roots if it’s left to go. We’ve done this routine to literally hundreds of trees with good effect and no issues.

Cheers
DAD sends

 

[River's Edge]

You think it's potted up too high above the pot?

Yes, on two counts. Not suitable for the health of the tree and not aesthetically correct for bonsai display.
The first count makes it difficult to keep the roots healthy and develop a proper root ball at the proper level which is the base of the trunk.
The second creates an overly wet core or a dry core depending on the differences between the old and new substrate.
If the tree was brought to me I would advise moving it to a deeper grow box and developing a better root system over time so it could be potted properly for display as the tree matures and is trained for bonsai.

 

[Kodama]

Yes, on two counts. Not suitable for the health of the tree and not aesthetically correct for bonsai display.

Thank you for this. I have an Anderson flat I can move it to. Should I wait till spring and also replace the other soil half with APL?

 

[River's Edge]

Thank you for this. I have an Anderson flat I can move it to. Should I wait till spring and also replace the other soil half with APL?

I would not be aggressive or change out tooo much more soil. But I would tease out gently more roots and soil to mix the two types of soil without damaging roots. This will also encourage the roots to migrate to the new mix. I would also carefully create some drainage holes in the centre core to even out the drainage and drying between the two masses. Three or four holes in the core will make a big difference for moisture and oxygen to help create healthier conditions throughout the entire root ball. That along with planting the entire root ball deeper in the Anderson flat will go a long way to creating a better beginning for the transition. Do remember to prop up the Anderson flat to ensure excellent drainage and gas exchange.
best wishes

 

[Kanorin]

Thank you for this. I have an Anderson flat I can move it to. Should I wait till spring and also replace the other soil half with APL?

While you can probably poke a few holes through the clay now, I’d wait for spring to do the repot and change out the rest of the media.

 

[Kodama]

Thank you for the clarification on that. I'll do the core drainage holes and get some cover medium on the top for better protection and will await for spring on the transfer.

Thank you all for the helpful advice. Much appreciated!

 

[TrimmyWhimmy]

Hinoki seem to like humidity. If you have a greenhouse, it would probably enjoy a holiday in there for a while.