AusBonsai

Hi Scott, I have a few starters as a bit of a trial in turface/zeolite vs diatomite/zeolite vs pumice/zeolite mixed 70/30. Still early days in trial (2nd growing season). Have JBP, figs and maples and doesn't appear to be much difference as yet in growth performance.

However the turface particles are quite small (probably too small) and it looks like it compacts down in the pots which may be an issue with good root development?

Moisture retention seems similar across all mixes.

I know everyone's got their favourite mixes and mine would have to be pumice/zeolite at this stage. Have a couple of more developed JBP in this mix which are just booming this season and look amazingly healthy.

Just my

My mix is even proportions of Scoria, small bark, turface and premium organic compost. My tridents and elms on this mix has amazing growth. Root development was tremendous at all level of the pot. They are healthy and abundant.
I have had trident coming back from near death in this mix from being in water logged in ground planting.

It would dry too quickly to grow in 100% turface I think.

Mr. Hagedorn says:
"Turface either stays too dry or too wet, and so it is not able to create a middle moisture level that enhances root growth.
this rocked my material engineering sense.

Hi bki, yeah I also read that post on Crataegus.com and I found it rather illuminating.
Sixteen months ago I repotted a couple of cork oaks in a mix with 50% turfacein a mix wit 50% turface and they have been struggling ever since. I have been really confused as to what their problem is. After reading Michael's post I think it may very well be the mix they are in. I have had issues with the turface drying out too quickly.
I only purchased this product one time when I could not get diatomite, and I am using diatomite once again for the bulk of my mix.
Cheers, Dario.

With my mix of equal parts of scoria, compost, turface and bark, I find it gets just dry enough to water at around 7pm when I have watered the night before on a 30 degree day with good sun.
I am trying to adjust it so that I only need to water once a day and if I have to water more than once a day, I will roll out the shade.

This is the way I am approaching it. This will be a problem in winter where we sometime get so much rain that the plant never get a chance to dry. In this case, I am planning to roll out the plastic sheets.
The water seems to run straight through the point when watering and this is my safeguard against over watering.

Do you think adjusting the mix so I just need to water once a day on a 30 degree day is a good plan? Does anyone see any problem with this approach?

Hi Dario,
I have been using Turface for a year or so as a trial. 40% with 20% coco peat, pine bark, 1/4 minus. Seems ok on chinese elm, Japanese maple, Yew & banksia. Drains well. Better than a "good" commercial mix.

Turface, diatomite, pumice and scoria have next to zero CEC therefore if you use these exclusively you have to treat your trees like hydroponic plants ie: they need a constant supply of nutrients arriving at the roots as the these media cannot hold important cations like ammonium, calcium, magnesium etc. They also have next to no buffering capacity. Thats fine if you have the time to feed every week with liquid fertilizer (and keep an eye on your pH) but note that a good rain or a couple of thourough waterings will wash most of it out. Thats pretty expensive on ferts and not so good for the environment either. One option is to use a controlled release feed like nutricote but you must add gypsum as these products do not contain calcium.
I have always had better results using sieved bark at at least 50% of the mix which adds a resonable level of CEC. Fine orchid bark is good and this type of mix will easily last 4 years. You could also moisten the inorganic components and sprinkle peat or zeolite through the mix. Both these have very high Cation exchange capacity. Akadama (clay) also has good to very good CEC.
One of the biggest benefits of using a composted bark in your mix is that it supplies iron to the plant (added as Iron sulphate) Providing enough iron to potted plants (without soil) is very difficult any other way so you may find your plants have darker leaves if you use high quality composted bark in your mix. Remember that (good) Potting mix companies have invested huge amounts of money on research, trials etc. so by all means adjust the wheel but don't try to reinvent it.
Well I've crapped on enough.

Always like to read what people are doing with soil mixes. It can be a very daunting area for new bonsai enthusiasts.

Stu wrote:Hi Dario,
I have been using Turface for a year or so as a trial. 40% with 20% coco peat, pine bark, 1/4 minus. Seems ok on chinese elm, Japanese maple, Yew & banksia. Drains well. Better than a "good" commercial mix.

Hi Stu, good to hear your trees are doing well. Yeah it seems quite a few people in the US and the UK use this product and seem to like it.
Mr Hagedorn must know what he is talking about though otherwise he wouldn't bother broaching the issue, he is obviously trying to help.
Anyway, of the two cork oaks that I planted in this mix, one of them is on the improve and I have started to feed it more and it is responding better. The other is still alive but it is not flourishing. It could well be some other issue that I have missed but I am not convinced as all of my other plants are healthy. During the recent hot spells Melb I noticed that those two trees coped the worst of all my plants due to them drying out much faster.
Thanks for your input treeman.
Cheers, Dario.

I'd have to second Dario's observation regarding trees in turface and the last warm spell. Out of the few soil mixes I am trialling the turface blend had the trees looking the thirstiest first

Hi Guys,

Just wanted to re-visit this thread and add some observations of a couple of tridents I have had in a 70/30 turface/zeolite mix for two growing seasons......they are struggling!!! They are at deaths door with dried up and shriveled leaves, while trees of similar age and development right next to them are booming in pumice/zeolite and kleensorb/zeolite mixes. (Have just read shibui's thread on root pruning and repotting 'out of' season.... looks like I have a couple of candidates to change over into another mix!)

Thanks foir the Update g.raft

hope the repotting and recovery goes OK

Ken

"Well there's ya problem" - Diatomite 70%/Zeolite 30% on the left vs Turface 70%/Zeolite 30% on the right

Yep, I know which one I'd go with...