Growstones

[RJSquirrel]

anyone ever use Growstones?
Growstone: Sustainable products for horticulture, container gardening and outdoor living

Bought a bag of this stuff to replace the Perlite in my mix. I couldn't find medium to large sponge-rock locally.That small stuff clogs my sink up and I have also tired of cleaning it up all over the floor. Looking for some different alternatives. This stuff is kind of pricey at 13 bucks for the 10 quart bag. But let ya know how it works out for me.


A potting media enhancer/amendment or used straight out of the bag. Anyway some very interesting specs on this material made from 99% recycled glass materials..

[Becca]

Never heard of it before but looks interesting. Maybe some of the more experienced growers will have some input on it.

[Anisa]

I might be wrong but isn't sponge stones the same thing as lava rocks? If I am wrong what is the difference between those two, except for a price and size?

[RJSquirrel]

sponge rock is coarse large chunky perlite.
lava rock is a rock from volcanoes.
lava rock will hold some water and works great for takin up space and holding plants down in the mix.

I potted up a few plants in my glass jar worlds with this stuff and I really like it so far

Testing the next few days to see how much my watering schedule will change. My schedule is worthless but keep me from over-watering.Ive gone to more scientific way of doing this with popsicle sticks in the pot.

Things always change and you have to adapt..and..
"Be the Orchid"

The south window is becoming brutal as I now get both east and west sun from 8 am till 6 pm and my plants need water everyday bec they gettin dried out faster.
This should retain more of the moisture and provide more air space than the perlite.

Plus this stuff is pretty for top dressing as it looks nice and we all know Im hung up on looking nice

[Ray]

Grow stones are pieces of foamed, recycled glass. Being a ceramic engineer and having worked with the glass industry for years, I really liked the idea, so got in some samples.

It's irregularity allows it to pack a little densely for my liking, but what really turned me off was the pH. In order to get the glass cullet to melt at an economical temperature and have the proper viscosity for foaming, they have to add alkaline earth minerals to flux it, and that makes the end result entirely too basic for most orchids to thrive in.

[Anisa]

Thank you so much for clarifying!

[Izzie]

Originally Posted by Ray

Grow stones are pieces of foamed, recycled glass. Being a ceramic engineer and having worked with the glass industry for years, I really liked the idea, so got in some samples.

It's irregularity allows it to pack a little densely for my liking, but what really turned me off was the pH. In order to get the glass cullet to melt at an economical temperature and have the proper viscosity for foaming, they have to add alkaline earth minerals to flux it, and that makes the end result entirely too basic for most orchids to thrive in.

Thank you so much for sharing this! I've been thinking of trying these, as they're popular in CO, but now I'll stay well away. Glad they're recycling, but it's too bad that they can't make it at a more neutral pH.

[RJSquirrel]

Their claim is the stones end result are ph neutral.
I haven't tested the PH and yea I know you cant believe all you read from manufacturers. I will run some water thru it then test it see if its truly PH neutral. I guess that how ya test it..

I like the way you can squish it down and it doesnt Float out of the pot when you water it. I have perlite in my bed its all over the house..Just floats everywhere in the air

Curious indeed and let you know If I kill anything with it..

Got to give it a go

[Ray]

They may have taken my advice on the pH, although they said there wasn't much they can do.

Try putting some water in a cup with the stuff and let it sit overnight. A pour-through won't tell you much, and does not replicate the conditions within the S/H pot environment.

[Izzie]

Ray- I, for one, really appreciate what you do for the industry. I'm glad to see a person that takes initiative to really address things!