Itoigawa Problems

[mrcasey]

My Itoigawas in nursery cans are doing terribly. They're leggy, not
producing strong growth or filling out, and they're dropping the most important branches.

They're planted in 1 gallon, black plastic nursery pots. They've been in these containers for at least 3 years. They get 8+ hours of direct sun per day. 24-8-16 miracle gro. The substrate is potting soil, perlite, and composted pine bark, all unsifted. I've never had much trouble using a denser organic mix to grow out in nursery pots. Checked the temperature just on the inside of the pot this afternoon, and it read 108 F.

Below each Itoigawa is a picture of the root ball.


Any ideas about why these are doing so poorly?








Below, is a Kishu in a bonsai container. It's growing in sifted pine bark, turface, and perlite. It's been super healthy and vigorous.

 

[MrFancyPlants]

The rootball photo looks really soggy to my untrained eye. Maybe less potting soil more pumice would help.
Hard to tell from the photo, but does the kishu have juvenile foliage?

 

[mrcasey]

The rootball photo looks really soggy to my untrained eye. Maybe less potting soil more pumice would help.
Hard to tell from the photo, but does the kishu have juvenile foliage?

The Kishu doesn't have juvenile foliage. It's perfectly healthy and growing with vigor. The reason I posted that picture was to show that not all my junipers are as unhealthy as the Itoigawa.

 

[Khalero]

You’re overfertilizing the itoigawa with such high synthetic npk values.

Miracle-Gro 24-8-16 is not a good idea for an Itoigawa with juvenile foliage. It is likely to prolong or worsen the problem. Organic, balanced fertilizers (lower nitrogen and slower release) are much better at encouraging mature foliage growth.

 

[mrcasey]

You’re overfertilizing the itoigawa with such high synthetic npk values.

Miracle-Gro 24-8-16 is not a good idea for an Itoigawa with juvenile foliage. It is likely to prolong or worsen the problem. Organic, balanced fertilizers (lower nitrogen and slower release) are much better at encouraging mature foliage growth.

I've been using the exact same fertilizer on my Kishu. The foliage is thick, compact, and robust. Is it just an Itoigawa thing?

 

[Dav4]

My guess would be the soil until proven otherwise... it's too dense and moisture laden/not enough oxygen in the roots zone, in my opinion. I'd rule out things like mites now, but moving forward, I'd advise getting these into a much more aggregate type of soil with lots of pumice +/- lava in the mix.

 

[River's Edge]

My guess would be the soil until proven otherwise... it's too dense and moisture laden/not enough oxygen in the roots zone, in my opinion. I'd rule out things like mites now, but moving forward, I'd advise getting these into a much more aggregate type of soil with lots of pumice +/- lava in the mix.

Agreed, poor drainage in nursery pots with that mix and high retention of moisture. Plus three years in the containers for young trees leads to compaction and declining health. At this time of year best step is to manage the watering to allow for some drying out between watering. Plan on repotting in the spring with a drier mix. Consider container that are better for root health in the heat, Such as the one used for your Kishu..

 

[Ruddigger]

You’re overfertilizing the itoigawa with such high synthetic npk values.

Miracle-Gro 24-8-16 is not a good idea for an Itoigawa with juvenile foliage. It is likely to prolong or worsen the problem. Organic, balanced fertilizers (lower nitrogen and slower release) are much better at encouraging mature foliage growth.

This is good advice.

 

[Deep Sea Diver]

Yep, media mix is too dense. Not so sure about fertilizer being an issue. Here is why I believe this to be so.

Here are a couple different types of developmental juniper.
- All in 85% perlite : 15% coco coir.
- All fertilized with Miracid (30:10:10) full strength with 5:2 Humic acid:kelp concentrations as recommended on product every 2-3 weeks from June through Sept. Also Osmocote Plus twice a year… and in winter storage… (our climate is mild enough the junipers grow a bit during winter)
- All in full sun

Itoigawa - Note one the difference in juvenile vs mature foliage. Never pruned. They have a mind of their own.


Kishu


Young Fudo. Again Fudo’s never pruned. A mind of their own.


Also a Kishu that has been in a 1 gallon nursery can for over four years. Never pruned. Measured at 110F on the inside of the pot last year.


Finally a shimpaku in 1:1:1 APL with Biochar. Been left to grow and create internal foliage for two years. Coming up on second external trimming. Wiring and more styling in fall.


Consequently imho seems to be no doubt about the media being too mucky… likely in both pots.

However it also seems the Miracle Gro 24:8:16 fertilizer, is not the issue for junipers… at least not in our location.

For what it is worth…

Cheers
DSD sends

 

[leatherback]

the substrate itself does not have to be the challenge, if the care is right. But are an be hard to get right if the tree it not taking up water.
How much do these get to dry up before watering? Organics seem to behave erratic in summer, and I find that the bottom of the rootball can be soaking wet, with the top appearing bone dry.

If a tree is not growing, it is not taking up much fertilizer and over-fertilizing is a risk.

Needless question probably, but you do not prune these do you?

 

[mrcasey]

the substrate itself does not have to be the challenge, if the care is right. But are an be hard to get right if the tree it not taking up water.
How much do these get to dry up before watering? Organics seem to behave erratic in summer, and I find that the bottom of the rootball can be soaking wet, with the top appearing bone dry.

If a tree is not growing, it is not taking up much fertilizer and over-fertilizing is a risk.

Needless question probably, but you do not prune these do you?

I take 2 or 3 small cuttings from these plants in March. I've also done significant shari work on them each year. The shari work has been done in June and September. I don't water on a schedule and let the top of the soil get dry before watering again. That said, I don't pull the trees out of the pots to examine the bottoms of the root ball every time I water.

I actually tend to have more trouble figuring out the water distribution in my granular mixes. I used to use chicken grit, turface, and pine bark. I recall times when the bottoms of pots would hold remarkable amounts of water and the top 1/2" would be bone dry. With something like promix or miracle gro potting soil, I find that the water wicks more evenly throughout the container.

 

[MrFancyPlants]

The kishu has a wonderful trunk. If it were mine I would develop weeping foliage. Like a weeping willow. It could be absolutely breathtaking in a round or scalloped lotus pot.

 

[MrFancyPlants]

I take 2 or 3 small cuttings from these plants in March. I've also done significant shari work on them each year. The shari work has been done in June and September. I don't water on a schedule and let the top of the soil get dry before watering again. That said, I don't pull the trees out of the pots to examine the bottoms of the root ball every time I water.

I actually tend to have more trouble figuring out the water distribution in my granular mixes. I used to use chicken grit, turface, and pine bark. I recall times when the bottoms of pots would hold remarkable amounts of water and the top 1/2" would be bone dry. With something like promix or miracle gro potting soil, I find that the water wicks more evenly throughout the container.

Mix in some long spaghnum in the granular mix, and you get the best of both worlds. Pumice holds a lot of water for its breathability and white color keeps the temperatures down in full sun..
Someone mentioned black nursery pots can get hot in the sun and set back roots.

 

[Khalero]

I've been using the exact same fertilizer on my Kishu. The foliage is thick, compact, and robust. Is it just an Itoigawa thing?

The itoigawa has stress foliage, the kishu doesn’t. Which means the kishu can handle the stronger fertilizer.

Personally I’d stop with miracle gro on the itoigawa and use a more mild organic one until the stress foliage is gone.

 

[Deep Sea Diver]

Getting the makings of a good Media and fertilizer tussle. I’m out…. But…

Gotta get some popcorn!

Watching
DSD sends