I'm pretty sure that cactus mix still holds to much water for potted citrus and needs to be thinned out with something such as perlite

I personally use a 1:1:1 mix for my potted citrus that contains (pine/spruce bark fines, Aquarium soil and crushed granite) the bark and soil are easily found at any pet store and the granite I found at a local hardware store.

My tree seems to love it! and it has such good drainage that its near impossible to over water.

The better Cactus/Citrus mix is fine here in hot/dry inland Southern California in a porous pot like Terracotta. It doesn't last long and I've seen some decline within a year if the pot wasn't big enough. I'm assuming you are wetter than that so the answer is that it might be better than what you have but not by much.

I'm sure you could improve it by screening over an insect screen to remove all the material under 1mm. Even better would be to screen over 1/8" screen, about 3mm in your terms. Anything under 2-2.5mm should fall through. That would mean you would be tossing more than half the mix you buy.

I see on the site provided that they offer orchid mix, which should get you pine/fir bark. I also see they offer coarse sand, and pumice in 1-3mm and 4-7mm. 2.5-4mm is going to be ideal particle size for a fast draining mix. If the sand is coarse enough, you should be able to make up a great mix for a damp climate. Just get rid of ALL material under 1mm as a minimum. If you can get rid of material under 2mm, so much the better.

The really important thing to understand from the excellent info provided by Al in the Water Movement in Containers thread is that you can go crazy trying to add coarse materials to a mix that starts out too fine. How much gravel do you have to add to pudding to get it to drain? LOTS!

This post was edited by GregBradley on Sun, Nov 2, 14 at 9:26

Thanks for the replies, really appreciated.

Seems like it is definitely not worth gettting that mix then and then screening it if I am to lose most of it.

Also it is very wet here in winter, so would be best to have a better draining medium.

How often do you guys water/fertilise your plants in these mediums?

Cheers

OK, I looked up the climate of Auckland. You have 10 times the number of rainy days per year as I do! The average amount of rain that we get here in summer is NONE, as in zero. Here in prime citrus county, the humidity in summer is typically single digits. Sounds like you need actual Gritty Mix.

If your only source of materials is the one provided, buy the 3mm sand, the 4-7mm pumice, and the orchid bark. Screen the orchid bark to remove any particles below 2.5mm and larger that 8mm. Mix them 1-1-1 by volume. That should give you an acceptable mix for citrus. Gently rinse off the current potting mix to get it off the roots without being too harsh on the existing roots.

Hi Greg,

Yeah Auckland is sub-tropical, so lots of rain and humidity, also the sun is uber strong. Not nice and dry like CA.

I think I have been able to find some bark fines, but asking some questions about it to see if it is right.

How often do you fertilize with the gritty mix?

Also is the pumice an alternative to the granite?

Cheers,

Ben

The Coarse Sand can be the same as Fine Gravel for Gritty Mix. They say it is 3mm, which is about the minimum you would want. I guess you would have to try a bag and see. Otherwise, Fine Gravel is sold as Chicken Grit at Feed Stores. Ideally you want sharp cornered rocks 1/10"-1/4", which converts to 2.5mm-6mm. Any particles below 2.5mm can hold water permanently in between particles. You can fill up a paper cup with their Coarse Sand and water, then punch a hole do allow the water to drain completely. When you insert a toothpick up into the mix, any water that drains was Perched Water and being held by the mix.

Pumice is an alternative for the Turface in Gritty Mix. It has lots of holes and holds water. Lava Rock is similar but seems to hold less water for a given volume as it has fewer holes that are larger.

I would be uncomfortable with any recommendation on fertilization as I'm clueless in that.

Hi,

I think I have found some pine bark fines (they say it is pine). Would I need to sieve this and remove the big stuff?

Says 5mm to 10mm.

http://www.bagboys.co.nz/products/landscape/bagged-bark-fine-3/

All the chicken grit I can find seems to be oyster/mussel shells. Will keep looking.

Cheers,

Ben

with my 1:1:1 mix that i mentioned, I find i need to water 2-3 times/week in the summer and 1-2 times/week in the winter(indoors)

I fertilize at every watering using Dyna-gro Foliage pro 9-3-6 at 1/2 tsp/Gallon of water in the summer and 1/4 tsp/Gallon of water in the winter. I find with the gritty mix the water drains so well that you need to apply more then the recommended amount of fertilizer. I've heard that with this mix its almost impossible to over water or over fertilize.

I am struggling to find foliage pro here in New Zealand. Contacted a potential distributor on the dyna-gro website, but I have never seen it here.

Have any of you put slow release fertiliser in your mixes? or does this just not work in gritty mix?

Cheers,

Ben

foliage pro is easy to find online, they don't sell it in my area either so i just bought it off eBay

I think to get foliage pro it would mean importing it.

Can I used slow release fertliser mixed and add liquid fertiliser as needed?

Also is Gypsum needed in my mix. I have seen some add it and others no?

Got the bark fines, pumice and aquarium gravel.

Cheers,

Ben