River Rock For Grow Media?

[Lindy]

I'm in the process of taking my garden over to DWC, and am thinking about grow media. Is there any reason I couldn't use clean, sterile river rock (which I could collect for nothing) as a grow media, as opposed to the expanded clay pellets (which I'd have to buy)?

[Restorium2]

I'm in the process of taking my garden over to DWC, and am thinking about grow media. Is there any reason I couldn't use clean, sterile river rock (which I could collect for nothing) as a grow media, as opposed to the expanded clay pellets (which I'd have to buy)?

Too heavy. The clay balls are light and porous. They are cheap and reusable. 

[bax]

you could use rocks, although most people are using plastic net pots to hold the plants, so you have to be sure your plastic net pots can handle the weight.

 

also since they are heavy rocks you want to be careful that they do not get shifted and crush the delicate taproot thus killing the plant. sometimes you have to lift the lid of the dwc bucket to see whats going on or to clean it or change air bubbler or something. heavy rocks can shift and break plant root.

 

you could probably use those lava landscape rocks if you dont want clay pellets. i think there are other alternative mediums as well.

 

people on the internet say:

you can just use foam like a pool noodle to hold the plant in place. no rocks/pellets at all. although you have to be careful about the roots being at the right height.

perlite

marbles / glass

 

search for alternative medium dwc in google for more results.

Edited June 2, 2017 by bax

[Restorium2]

You would have to test each rock with a few drops of ordinary white vinegar. If the vinegar foams, the rock is calcareous and this will effect the hardness and pH of the nutrient solution. You would be chasing your tail all day long trying to adjust the pH. 

[Wild Bill]

I've grown in pea gravel. The major drawback is the weight. Other than that I had no problems.

[Highlander]

I tried lava rock. Terrible experience. The sharp edges were horrible on the roots. I also tried a product called "the rock that doesn't roll." This was marketed as a solution to hydroton but was very heavy. I hated hydroton...the washing, pebbles bouncing all over if you spilled it. I tried bare root in a 2" net pot with the bottom cut out and a foam insert - no grow medium at all. This was the winning idea. I use tomato cages attached to the bucket lids for support. This has worked well for about 7 years and has made life so much easier.

[Lindy]

you could use rocks, although most people are using plastic net pots to hold the plants, so you have to be sure your plastic net pots can handle the weight.

 

also since they are heavy rocks you want to be careful that they do not get shifted and crush the delicate taproot thus killing the plant. sometimes you have to lift the lid of the dwc bucket to see whats going on or to clean it or change air bubbler or something. heavy rocks can shift and break plant root.

 

you could probably use those lava landscape rocks if you dont want clay pellets. i think there are other alternative mediums as well.

 

people on the internet say:

you can just use foam like a pool noodle to hold the plant in place. no rocks/pellets at all. although you have to be careful about the roots being at the right height.

perlite

marbles / glass

 

search for alternative medium dwc in google for more results.

 

 

Don't know if I'm looking for alternatives as much as I'm being a cheapskate ;P

[Lindy]

Thanks for the great input guys! I may give the pool noodle thing a go... I think I may have one out in the barn

[semicaregiver]

I tried lava rock. Terrible experience. The sharp edges were horrible on the roots. I also tried a product called "the rock that doesn't roll." This was marketed as a solution to hydroton but was very heavy. I hated hydroton...the washing, pebbles bouncing all over if you spilled it. I tried bare root in a 2" net pot with the bottom cut out and a foam insert - no grow medium at all. This was the winning idea. I use tomato cages attached to the bucket lids for support. This has worked well for about 7 years and has made life so much easier.

Love this approach.  I have used it for several years in both DWC and aeroponic.    

[Restorium2]

Think food grade when you are deciding on unconventional items that were not intended to be used for growing. Especially on a medical grow. Pool noodles would degrade and leave bad stuff in your product. 

[bax]

yeah, please use food grade if possible, resto is correct.