Soil Mixture Worry- Need help Please

[Ryan1979b]

Hey all, I have just potted a Shimpaku with a new soil mixture but i'm not sure if it is ok. Previously I have been just using premium Bonsai mix which wasn't doing the best. I have used a combination of 1/2 Premium potting mix - 1/4 Course sand (propagating sand) - 1/4 Chandlers litter clay (attapulgite cat litter) drained of fines. I is a bit heavier and seams to be staying damper for a lot loner. I was wondering if this would be a bad mix fop my Shimpaku as I don't want to use a mix that will cause root rot.

Any advice would be great, I have just re-potted with only minor root pruning so maybe a soil change could be ok if necessary

Cheer all

Ryan

[john tapner]

Ryan, I would advise getting some of Ray Nesci's potting mix. 60% of this, add a good handful of zeolite, some blood and bone in the mix, and about 20% of course gravel. Use additional course gravel as top dressing on the pot. Sieve the gravel before use to remove dust and small particles. If you intend showing the tree remove the course gravel and replace with finer particle gravel and with the addition of patches of good quality moss.
I have been using this mix for years now and the water drains well and the tree seems to like this environment.

Go for it

John T

[aaron_tas]

i reckon your mix should be fine.

if the trees not drinkin it, then dont make it drink...

[Tim]

You guys know ur stuff. The tree could be relaxing and not using much water. Was it repositioned after repotting? Mine stay in the shade for 1 or 2 weeks. I use diatomite with 10% debco for the larger trees and sieved 2mm diatomite for the wee ones. I find that attapulgite clay breaks down quickly and therefore dont use it. Check conditions first then potting mix.

[kcpoole]

Talk about opening a can of worms

The only one that can categorically say thay th mix you use is OK is YOU.
Everones environment and watering / maintenance regimes are different which makes it impossible to provide definitive advice.

Is this the same mix as in other trees in the same environment? Are they also wet? if so then add some more stuff to make it less water holding and open it up more ( decomposed granite),

if is the only one with the problem then maybe try watering it less than the others. Might have less efficient root system

Ken

[Ryan1979b]

Cheers, its a new mixture, the only other plant I have used it on is my Casuarina Which I collected & is a water tray So its hard to compare, but is doing fine so far. I will keep an eye on it & see what happens. I'm fairly new to soil as I have only been doing it a little while so I'm still pretty wary & don't want to make my plants suffer and loose stock. I know I have a lot of white crushed granite that I use in my fish tanks which could be a good medium, its about 1-2mm. Its about $20 a bag for 20-25 kilos, it might be work using instead of the clay or would you recommend something a little larger to allow more water flow. I'll keep you posted anyway on how they are going.

Cheers all

[Mojo Moyogi]

Ryan next time you repot the shimpaku, lose the kitty litter, I've said it a few times that it is crap and putting it in a glass of water to test it is flawed and proves as much about Attapulgite's suitability for making rocket fuel as it does about testing it's suitability for bonsai. Attapulgite is way too soft and inconsistent for potting media, even in nursery pots. Try a 50-50 mix of 2-7mm diatomite and a good quality pottong mix, sift out the fines, you should have a fairly well structured, free draining mix.

Cheers
MM

[Espresso]

I have been using a very course mix over the last 10 years or so and decided to try the Debco Bonsai miz - So far so good.

[Bretts]

As KC said there are many variables. I tried out a new bulk mix this year that was crushed terracotta pine bark and cow manure. The first things I used it on was various trees that came out of the ground and went into standard nursery pots. It drained great.
I then used this mix with a little more care on a Japanese Hornbeam in a terracotta. I took a bit of extra care thought as if that won't drain. Watering the tree in I found that the water sat on top for a while. Begrudgingly I removed the tree from it's pot and tried again same thing Gave it one last try and was still the same. As the mix worked fine in the nursery pots I figured it was the single hole of the terracotta pot that was the difference. I figured in the end that as the terracotta pot evaporates through the wall that it would be ok.
This tree is now going great and is one that I now water every day. Recently I was very impressed that it sustained heat that although sun burnt a couple of leaves from extreme heat (cold climate tree) it did not sufer the effects of drought that would have shown up as leaf burn around the edges of the leaves.
Your mix sounds ok although a little heavy/organic for a conifer I would think.
You state this has just been repotted. I would just not water until it needs it. Depending on what sought of root ball you put into this mix and considering it has just been repotted it may be prudent to inspect the actual root ball(with your finger) to make sure it is moist. When it does start to dry water well ensuring you flush out as much as you can then wait till it drys out some what again. If this continues to be longer than 4 days before it starting to dry out, say one month then there is a problem and an emergancy repot into a very coarse mix that will dry out may be prudent.

The health of the tree is also a big issue. If the tree does not grow vibrantly alot of the soil will sit unused and not dry out.
I had a trident this year that was not mine and I did not realise it was so weak. After a major rott reduction and repot. It refused to dry the soil mix out which I think was a little heavy anyway. I removed after it had leafed out and replaced in a 3/4 crushed terracotta to 1/4 organic. I saw that roots had started to grow at the time and am very happy now that I can water almost every day although the health is still not there yet.

You have not mentioned what it is potted in? As I have hinted that can be a big issue. As I have stated Chandlers kitty litter works fine for me I may not use cow manure like stated above again though. Made a great fertile mix but now wonder if it has something to do with my exaggerated fungal problem this year. Major pruning from field to pot may not be great sitting in cow poo while it is waiting to grow new roots

[stymie]

Grit for pines should be coarse. 5mm particle size at least. They can exist happily in little more than that. Something that may be termed 'dirty grit'.

[Bretts]

Thats intresting Stymie. I can understand a grity mix but why not smaller than 5mm? There has been advice around here recently that sand(1mm propagating sand) is a great additive for mixes and I would think this would work just as good for conifers if not better than deciduous trees. It has made alot of sense to me that a fine inorganic mix could be very binificail. Lots of drainage yet the fine mix allows many root paths! I have been moving away from anything above 3mm.
I have been thinking latley about the correct size pot to tree that will allow the tree to use up the water in the pot and be healthy and thinking that it seems feasible that a larger pot would work just as good but still have the extra room if a "more than usual" draining mix was used?
It may not sound like the same subject but in my context it is. Why not use a larger pot if you can make it dry out as fast as a smaller one?