Wanted Chunky sponge rocks and charcoals source

[Ray]

https://greenbarnorchid.com/

 

[Russ1992]

I looked up the archives, it was "mother earth perlite", 4 cu ft each, but it says unavailable now. there's a lot of other options on amazon but I don't know the vendors or products. Not sure sponge rock varies that much though, as long as it's the correct size.

Personally I really like sponge rock for the slippers for the air retention. I have a pile of old LECA and while they are both inert products I do not believe LECA holds that same quantity of air. yes sponge rock can be crushed, but most people don't pot paphs/phrags in a fashion where you should be crushing them.

The air spaces for perlite #4 are definitely larger than those I have seen for leca but leca probably gives just as much air as #3.

Motherearth #3 and #4 can be purchased through other retailers

 

[Greenpaph]

Sponge rock, perlite, pumice, lava rock... they are all largely the same thing. Lava rock just has a higher mineral content while sponge rock is principally silicon. I am have excellent results with lava rock so far. Papsh (even seedlings), Catts, Restrepia, Masdevallia, Ansellia, Oncidiums are all taking to it. Only the Lycaste objected.

What do you use for Lycaste?

 

[TyroneGenade]

What do you use for Lycaste?

I was using sphagnum in a basket. It didn't really like that either but it absolutely hated the lava rock and died.

 

[Ray]

The air spaces for perlite #4 are definitely larger than those I have seen for leca but leca probably gives just as much air as #3.

Motherearth #3 and #4 can be purchased through other retailers

That’s a little too broad of a statement for my mind.

The most open volume occurs when all of the particles are perfect spheres of identical size, at roughly 40% open. Any size or shape variation reduces that.

Having said that, perlite, being sharply jagged or “craggy” might interlock sharp edges to create larger voids, but it’s also quite friable, so can crumble over time, ultimately packing more tightly.

 

[Sky7Bear]

That’s a little too broad of a statement for my mind.

The most open volume occurs when all of the particles are perfect spheres of identical size, at roughly 40% open. Any size or shape variation reduces that.

Having said that, perlite, being sharply jagged or “craggy” might interlock sharp edges to create larger voids, but it’s also quite friable, so can crumble over time, ultimately packing more tightly.

And is it good, then to seive, say Hydroton, to get more equal size spheres, or is there a brand that has equal sizes? Hydroton is quite variable.

 

[Ray]

You’re right, Harvey.

It used to be that the “standard” or at least typical LECA was 8-16 mm. The stuff I sold as PrimeAgra was the 10-16 mm cut, but I find that most are even more variable these days.

That said, in my experience, uniform, perfect spheres are not necessarily the best potting medium, as they can move too easily, leading to wobbly plants. A little bit a size and shape variation helps reduce that.

The (apparently) one-and-only hydroponics shop in Wilmington carries a product called CYCO Hydro Rocks (or something like that), and it’s pretty good.