Has anyone tried using porous calcined clay products like Turface for their potted citrus? I was thinking of trying a blend with this and thought I'd check for other's experiences.
http://www.turface.com/sites/default/files/Landscape_Brochure.pdf

Or should I be thinking a LECA expanded clay product like Hydroton?

They have been used. Both are just "OK" with small trees in small containers. There are much better mediums to use. - MIllet

I use Leca, that balls for Hydroculture and also Perlite for my soil mixes.

Millet, my interest is in a soilless mix that will last as long as I do. Any specific suggestions for better products? Leca seems like a neutral pH version of the scoria you were evaluating...not true? I know that leca is more expensive...other downsides? I was thinking of a mix, perhaps with small homemade hardwood charcoal particles spaced to help slow the water and help guide it to the leca as one experiment.

Sanguinello, do you blend your leca or use pure? Are you doing that with your potted citrus, or with hydroponic systems?

I just add Leca and Perlite to a soil mix made of humus, compost and pine bark.

That is for common pots, no hydroculture.

Greg there is certainly nothing wrong with experimentation. I do a lot of it myself. In the end the scoria experiment of mine, did not work out as well, as I had hoped so I moved on. Now I am experimenting with ground Cedar mulch blended with peat moss as a medium for container trees, which so far seems to be working outstandingly, but it will take a year to determine its full value as a medium. For orchids, streiaght cedar mulch has worked so well that I have transplanted 15 of my orchids into it. There are certainly many other ingredients and conbinations that could be tried and evaluated, but it takes people interested in searching for them. Let is know what you think of LECA after you have had time evaluating it. - Millet

Synovia, during the summer how often do you have to water the container? Also, how large is the tree and what size is the container? - Millet

I probably water the trees twice a week during the summer. They're on a deck that gets full sun. That will probably become more often as they get bigger.

The largest is probably a 3' or so tall mandarin thats pretty beefy for its height. I think its a 12 or 14" pot.

The clay holds quite a bit of water, but the rock and bark tend to keep thinks structured enough that the roots get plenty of oxygen. You pretty much can't overwater the stuff because it drains so well.

There are a lot of people using this mix for woody plants, and container trees on Gardenweb (search for Gritty Mix). I'm only a year in with it, so I can't give a ton more experience. So far, so good though.

What brand of kitty liter? Online I've read that people have luck with Walmart's Special Kitty. Seems to be calcined enough that it holds together when wet, but that not calcined enough to take freeze/thaw cycles...it'll turn to mush. But with potted citrus that shouldn't be an issue since they need to come in before that so they don't turn to mush! I'm tempted to play with it.

I picked up a bag of Turface and planted Poncirus seedlings into it strait, as well as into a series of blends. Waiting for my bag of LECA to arrive. The turface looks pretty promising, but using it strait will make for a very heavy pot. If I end up with that I'll have to outfit my appliance dolly to move my pots in and out of the sun room each year...or else I'll have to start a serious training program at the gym.

I'm also really looking forward to hearing how the cedar holds up over time.

The main problem with the Gritty Mix is its weight. It can work for small trees and containers, but as the tree grows and needs to be transplanted into a large container the gritty mix's weight becomes unmanageable. Plus as the tree grows larger and requires more water, a grower using the gritty mix must very frequently water the container. - Millet

I'm using some cheap stuff I found at Petsmart. I think it might be their store brand, but I'm not sure. I don't have any bags on hand, but I can check next time I'm there.



Gritty is definitely heavy. I don't have any really big trees, but I can see how that would be an issue if you need to move one. That being said, being heavy means you're less likely to have it tip over in heavy winds. Thats a big concern to me on the coast.

If you wanted to reduce the weight, I'm sure the grit/pebble part could be replaced by something lighter. We'd just need something lightweight and inert that won't absorb water. Lava rock might work. You'd probably have to tweak it a bit because lava rock will definitely hold a little bit of water.

Maybe some sort of bulk industrial product. I'm thinking something like tile spacers:




As to the watering, we get pretty bad rains in the spring, and I was having all sorts of problems with root issues using more traditional mixes. With the gritty, the problems have all dissapeared, and I haven't found watering too onerous.

With my chemical engineering training my mind always goes to distillation collumn packing and I think if someone could make the right porous ceramic saddles without it somehow costing a fortune that they could be great. Heres what those look like:
http://image.made-in-china.com/4f0j00gBRtCQyzaHcZ/Ceramic-Saddles.jpg
They could be pretty thin and so not be very heavy, yet hold and distribute water and not allow mixes with them to collapse over time much. You could make these with a pasta maker, a pottery kiln and the right secret recipe to give good pore structure. Just dreaming a bit.