Best potting mix for macadamia/ proteaceae?

[SeaWalnut]

What would be a good soil mix for macadamia?
I dont have macadamia but somme related trees,Gevuina and i need to transplant them to bigger pots.
I have perlite,yellow clay,black clay,sandy soil,biochar,simple charcoal , manure and coarse sand.

These proteaceae dont like much phosphates in the soil but Gevuinas are more tolerant of normal levels of phosphates.
Lowet phosphates i can achieve by maintaining a lower ph( acidic) but im also thinking (this is my own idea)to mix somme red iron oxide powder into the soil wich will bind and make the phosphates non available.

[SeaWalnut]

Something you dont see every day .
From top to bottom:
1- Black clay soil ( from 20 cms deep because on the top it has too much phospate.With depth phospate is lower.
2-Coarse sand,construction grade and the white patch is perlite.
3- compost with 20% biochar and 300 grams of red iron oxide.To the right ,the brown part is the compost allready mixed with the iron oxide.
The purpose of the red iron oxide ( rust) is to lower the phosphates a little and because i got tired to put iron nails into the soil 
Note:Do not copy my mix with iron oxide because im doing an experiment.

The soil was then watered with rain water plus 2 mg/ litter of pyrolygneous acid( humic acid).The ph of the water was 4,5 .

The water that came out of the pots was red.
 
Because the water was too red colored,i couldnt make tests so i tested the compost only.Nitrogen and phosphorus levels.

[SeaWalnut]

One bad thing ive noticed is about the perlite.
Perlite killed the earthworms because it acts like small shards of glass.
So if you want to have earthworms to dig a network of tunnels in the soil,you cant have them if you have perlite.
There werent manny earthworms in the mix as i colected the most and released them before i added the perlite( i knew its not good for them).
Hope that perlite works to repel snails .

[achetadomestica]

I never noticed worms avoid soil with perlite?
I am sure there is allot of perlite in my potting soil and worms?
Maybe the perlite loses its edges?

In the past I have failed miserably with macadamia trees.
They seem to prefer very low ph like blueberries.
I also had high salt in my deep well which caused major issues.
I have now switched to a shallow well and I recently purchased
several rare cultivars of macadamia and I dug a big hole in my sand and filled
with lambert potting mix and perlite. So far two of the small recently
air layered trees are putting out new growth. I hit them with some
holly tone and they are a little yellow but it was nice to see new growth.
I have two more to plant later after they develop roots better.

The place I got my trees uses 8-4-8 synthetic fertilizer with micros and
they throw a handful of Tiger 90 sulfer every 3 months. They water twice a day
smaller amounts of water. 

[SeaWalnut]

I never noticed worms avoid soil with perlite?
I am sure there is allot of perlite in my potting soil and worms?
Maybe the perlite loses its edges?

In the past I have failed miserably with macadamia trees.
They seem to prefer very low ph like blueberries.
I also had high salt in my deep well which caused major issues.
I have now switched to a shallow well and I recently purchased
several rare cultivars of macadamia and I dug a big hole in my sand and filled
with lambert potting mix and perlite. So far two of the small recently
air layered trees are putting out new growth. I hit them with some
holly tone and they are a little yellow but it was nice to see new growth.
I have two more to plant later after they develop roots better.

The place I got my trees uses 8-4-8 synthetic fertilizer with micros and
they throw a handful of Tiger 90 sulfer every 3 months. They water twice a day
smaller amounts of water.

Macadamia and these proteaceae dont like phosphorus.
Do not fertilise with phosphorus because its bad for them .
I have Gevuinas not Macadamia ,and they are south american proteaceae wich are more tolerant of phosphorus.
The red iron oxide i use it to reduce the phosphorus from the soil.
At low ph ,the phosphorus becomes non available (acid
makes the iron to rust and then the iron oxide binds the phosphates) ,thats why they like low ph.

As for the perlite killing eartworms,ive bought natural perlite wich is a volcanic rock ,basically volcanic expanded glass.
It had a warning that said to not rub your eyes with hand while handling it because can damage your eyes.Tiny glass shards that could stuck into the eyes probably.
I treated it similar to diatomite soil that has small silica glass like threads and its used to protect plants from worms and caterpillars.

[SeaWalnut]

Chlorosis in macadamia( and for my gevuinas) its caused by too much phosphorus in the soil.https://www.tandfonline.com/doi/abs/10.1080/01904168809363793

Meanwhile i have found somme realy nice and weathered soil verry low ( 0) in phosphorus from an iron pan made by an old stream of underground water .
http://tropicalfruitforum.com/index.php?topic=36791.msg378743#msg378743

[ScottR]

Thanks for post on iron addition to soil to help bind phosphorus I have 10 or so macadamia's and one variety I have called L-4 suffers from chlorosis. I forgot about adding iron to soil to correct this problem. Also, I have tried for many years to grow gevuinas and sad to say have killed them to many times. In California we had peat moss to soil for lower ph and I use pumice in potting mix and still have worms!
Can you share your source of gevuina seeds they are getting hard to find these day's, used to be site from Chile where there endemic but no longer have seeds available.

[SeaWalnut]

Thanks for post on iron addition to soil to help bind phosphorus I have 10 or so macadamia's and one variety I have called L-4 suffers from chlorosis. I forgot about adding iron to soil to correct this problem. Also, I have tried for many years to grow gevuinas and sad to say have killed them to many times. In California we had peat moss to soil for lower ph and I use pumice in potting mix and still have worms!
Can you share your source of gevuina seeds they are getting hard to find these day's, used to be site from Chile where there endemic but no longer have seeds available.

Gevuina seeds these days are impossible to find for sale on the internet.I got them from a friend .
A few years ago i paid a lot on somme gevuinas from USA that were for sale on Ebay and the seeds were old,none germinated.
If you want to buy seeds be carefull not to buy older than 6-12 months seeds.
They are verry easy to germinate and they are easily grown from cuttings.
Its a verry beautifull tree,verry cold tolerant but doesnt like drought.

The perlite ive used killed all the worms but its perlite( expanded volcanic glass) not pumice,LECA or vermiculite.
It had a warning on the label wich said not to rub your eyes afyer handling the pelite because of the risk of getting blind from the tiny glass shards.
I wouldnt use perlite again except as a worm and snail deterrent wich you would need for gevuinas.Slugs ate like 70 % of my gevuina seedlings before i added the perlite.

[SeaWalnut]

Thanks for post on iron addition to soil to help bind phosphorus I have 10 or so macadamia's and one variety I have called L-4 suffers from chlorosis. I forgot about adding iron to soil to correct this problem. Also, I have tried for many years to grow gevuinas and sad to say have killed them to many times. In California we had peat moss to soil for lower ph and I use pumice in potting mix and still have worms!
Can you share your source of gevuina seeds they are getting hard to find these day's, used to be site from Chile where there endemic but no longer have seeds available.

Rarepalm seeds has them now.
https://www.rarepalmseeds.com/gevuina-avellana

[ScottR]

Thanks for informing me!