Coco Peat

[one_bonsai]

Do you add it to your substrate dry or wet?

[shibui]

I don't add any sort of peat, wet or dry.
What are you growing that needs peat in the mix in Melbourne?
I know it is possible to manage trees in almost any substrate but peat of any sort will retain more moisture which has the potential to cause root problems if not managed carefully.

[one_bonsai]

What are you growing that needs peat in the mix in Melbourne?

Junipers and Cedars. I plan to grow some this spring in a zeolite/diatomite mix and wanted add some coco peat for a bit more water retention.

[shibui]

Good luck with the mix. Just seems strange to make an extremely open, well drained mix and then add something that makes it less so. I'm sure we will all be interested in your results after a year or 2.

How to add will depend on how you buy the peat. I usually get compressed bricks which need to be soaked in warm water so it expands back to full size. I would add that when still damp.
If you have natural coco peat you could probably mix it dry but damp is safer -

Please be aware that all soil mixes should be damp when you handle them. All organic and some inorganics have the potential to carry bacteria and fungi that could be harmful or even cause death. See the labels on bags of potting mix. They do not write that stuff just for fun. There is a real risk of things like legionella in potting mixes. All potting mix should be damp to reduce the risk of breathing airborne particles.

[one_bonsai]

Just seems strange to make an extremely open, well drained mix and then add something that makes it less so.

I'm worried it will dry too quickly so I think I need some organics in there

[robb63]

Its very difficult finding a good Diatomite that won't break down into fine clay.
If you add a good quality potting mix to the zeolite/diatomite the trees will do well.

[Ryceman3]

I use coir peat as part of my standard mix (for everything from pines to deciduous), I even add extra for thirsty trees like natives - they seem to like it. I think it depends on where/how you grow. My trees are on a roof getting maximum sun/wind exposure. A bit of extra moisture retention is a blessing up there. I soak the block as per instructions. It’s what you’re comfortable with that is the key... I know it was part of the mix that Mr Bowie used when at the arboretum in Canberra... at least that’s what I think I remember reading!
... if it’s good enough for him...

[regwac]

I use coco peat as a part of all my mixes ( one part in six mostly ) and I have two Hawthorns which have been in pure coco peat or coco peat and zeolite for a number of years without problems . My climate is colder and drier than Canberra .

[treeman]

Nothing wrong with some peat for thirsty species (deciduous and fruiting) Coir is not the same as real peat moss though. Advantages are that it does seem to have the water repellent properties of peat moss. Disadvantages are that it can contain high levels of chloride, and is extremely high in potassium - sometimes so much as to cause magnesium deficiency and it's pH is already rather high. I don't just wet it but soak it in a bucket until it sinks (that can take several days) then drain and squeeze it out and soak again in some water containing epsom salts. When it's dry you can sieve out the dust and use it without too many further problems. When it first came on the market, coconut was hailed as the best medium for orchids. Now after a few years of trials, no one wants to touch it anymore.
Note that mycorrhizae loves coir!

[longd_au]

I use coir peat in my mix of diatomite, scoria, pine bark and zeolite. Without the coir, the mix dries too quickly in summer. I am in Melbourne.
I experimented this mix for two years with my Elms and Tridents and both seem to like it. I have not had any trouble. I water once in the morning but do move the plant into shade during days above 35 degrees. I also find the black birds spend less time digging into this mix compared to those using potting mix.

I soak the coir for a day and squeeze out the water before adding to my inorganic. After reading Treeman's post, I will soak twice next season.
Thanks Treeman.