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Wanted Chunky sponge rocks and charcoals source

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Tom-DE

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Would like to know where I can find good quality coarse sponge rocks(0.5"+ to 1") and charcoals(around 1"). Thanks
 
For coarse sponge rock use your search engine and put in there ‘hydroponic stores near me’. There is usually a few that are fairly close to you. You can always call ahead to be sure they have it in stock, although truthfully I’ve never been in one that didn’t have at least a large bag or two. Many of these stores will often order anything that they carry and you want and have it sent to their store for free, or to your home at a fee. It’s also a great place to get net pots.

Now charcoal is another story. I bought a few large bags from Parkside nursery when they were closing down. Glad I have it, however there is little consistency to size.
 
Thank you, Bob. Someone mentioned about hydroponic store to me also. I will check with them for sure.

When I got rid of my collection, I gave away almost all of my supplies(pots and potting materials, including a 50-pound bag of charcoals)...now I am low on supplies after recent repottings and potted up new plants. I think I can do away with fewer charcoals if I can have some very coarse sponge rocks.
 
a while ago I got huge bags of #3 and #4 sponge rock via amazon. maybe not a lifetime supply, if I'm lucky, but definitely a 5-10 year supply.
Care to share the name of the seller or brand? I am totally out of touch with the current market...the last time I bought my orchid supplies was over 10 years ago from a local grower(when he was going out of business).
 
I use the Green Barn Orchid Supply store in Delray Beach Florida. They have just about everything an orchid grower could possibly need. They carry many different sized bags of ingredients as well as different grades, fine, medium etc. Charcoal and perlite shipped dry really do not weigh all that much. Delivery is within a week.
 
@Tom-DE have you considered using LECA instead of sponge rock?

Water holding capacity is similar and it won’t crumble over time. It is heavier, but not enough to be an issue in a blend.
Ray, I tried that before(long long time ago) and I didn't like it. By the time I got rid of my plants, I still had 80% full bag of it left(more than 1 cubic foot).
I am not crazy about the quality of the sponge rocks that I have and a few charcoals left, that is why I am looking for new source for them, but with only 40 plants, I am not in the panic mood yet.
 
Care to share the name of the seller or brand? I am totally out of touch with the current market...the last time I bought my orchid supplies was over 10 years ago from a local grower(when he was going out of business).
Mother Earth is the brand I bought off Amazon…#4 Perlite.
BIG package 4 foot tall and very reasonably priced
 
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.
 
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.
You are right for the most part...lava rocks are quite different and I used to use them for Vanda in basket.
I am kinda old-fashioned. If things are working well for me, I normally would not change it. I did find some #3 sponge rocks on OFE website, which I got some supplies from them before. If I don't find #4, then I will order #3 from OFE in FL.

Thank you all for all the info.
 
Care to share the name of the seller or brand? I am totally out of touch with the current market...the last time I bought my orchid supplies was over 10 years ago from a local grower(when he was going out of business).
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.
 
Thank you, Jason. I like sponge rocks for the same reason also...unfortunately, the quality does vary a little, some can be crushed easily and that is why I try to buy the chunky ones if I can.
 
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.
You're right. The airiness of LECA comes into play with the spaces between them, not within the particles themselves - they are superior at holding water.

If you had 100% spherical particles of the same size, that would be roughly 40% open space. Any irregularity in size or shape decreases the open volume.

Don't get too confident in the airiness of perlite, however. The finer the particles and the more irregular the size and shape, the smaller the voids will be between the particles, and surface tension can hold them full of water.

I am tempted to try an experiment using glass marbles that have been tumbled to roughen the surface to a "sea glass" texture. The fine striations in the surface would remain wetted, but the void spaces would remain open at all times.
 
I second Green Barn Orchid supplies! I’m actually putting an order in with them this week! Their stuff is very reasonably priced even if their website is lacking functionality 😕
 
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