Crushed Lava In Potting Mix?

[Butch]

I was cleaning out my garage, and I came across 2ea, maybe 5-10# bags of 1" lava pieces... I think these were meant for a gas BBQ ,but for some reason never used... Would these be worth using in a potting mix?... Otherwise they'll probably go in the trash..Thanks,

Butch

Edited March 25, 2021 by Butch

[Philly J]

2 minutes ago, Butch said:

I was cleaning out my garage, and I came across 2ea, maybe 5-10# bags of 1" lava pieces... I think these were meant for a gas BBQ ,but for some reason never used... Would these be worth using in a potting mix?... Otherwise they'll probably go in the trash..Thanks,

Butch

I use clay leca to line the bottom of my terracotta’s, I’m guessing this would be similar for the drainage for sure, but is it treated with anything for a BBQ?

[Silas_Sancona]

5 minutes ago, Butch said:

I was cleaning out my garage, and I came across 2ea, maybe 5-10# bags of 1" lava pieces... I think these were meant for a gas BBQ ,but for some reason never used... Would these be worth using in a potting mix?... Otherwise they'll probably go in the trash..Thanks,

Butch

1"  might be a bit big but if you can crush it down to 1/2 inch or smaller ( i put chunks like this in a plastic bag and crush w/ a hammer ),  will work fine in soil mixes.  Provides the same advantages as Pumice: Providing better drainage, allowing more air into/through the mix/ to the roots, retaining some moisture and releasing slowly between soakings.

[Butch]

11 minutes ago, Philly J said:

I use clay leca to line the bottom of my terracotta’s, I’m guessing this would be similar for the drainage for sure, but is it treated with anything for a BBQ?

I don't know, but I doubt it... After all, you are going to ingest anything that may be given off during cooking... The pieces look to be bare rock..

Butch

[Butch]

1 minute ago, Silas_Sancona said:

1"  might be a bit big but if you can crush it down to 1/2 inch or smaller ( i put chunks like this in a plastic bag and crush w/ a hammer ),  will work fine in soil mixes.  Provides the same advantages as Pumice: Providing better drainage, allowing more air into/through the mix/ to the roots, retaining some moisture and releasing slowly between soakings.

That is a good idea.. I figured the 1" might be a bit to large...

Butch

[Frond-friend42]

I would recommend not lining the bottom of pots with rocks. Mix the Rick's into the soil evenly.. Volcanic rock has been used with considerable success by palmists.

Lining the bottom with rocks actually does not improve drainage. It interrupts the column of water, causing it to cling to the soil rather than entering the bottom rocky zone. 

[PalmatierMeg]

Is it red or black lava rock? I've been told red lava rock contains higher amounts of iron that are unhealthy for palms. Jeff Marcus uses black lava rock to grow his palms.

[Butch]

It is black, and I'll mix it in the next batch of "mix".... Thanks for the suggestions, folks... I hate wasting anything...

Butch

[Missi]

I use 1/4" black lava rocks in my palm and smaller Aroid soil amendment. I've always been iffy about using red lava rocks, but there is a commercially available orchid mix that big box stores carry and it includes it. For what it's worth, I use this mix as part of the potting media for my larger epiphytic Aroids and haven't had issues as of yet.

[Silas_Sancona]

On 3/25/2021 at 3:35 PM, PalmatierMeg said:

Is it red or black lava rock? I've been told red lava rock contains higher amounts of iron that are unhealthy for palms. Jeff Marcus uses black lava rock to grow his palms.

Interesting, have never heard that red might have any potentially negative effects on plant growth vs. using black colored cinder due to a higher iron content.. Is used extensively in/ sold in bulk for soil mixes by a few nurseries here. Everything seems to love it.

As far as Hawaii, both types are found on the islands. Jeff may be using what is locally sourced, and looks better.  Prefer black over red for the appearance factor myself, at least when it comes to dressing the top of display plants. A product sold there in FL. often called " Timberlite " / " Firelite " looks even better ( Earth-toned colors ) Is a touch lighter than regular cinder and can be pulverized to smaller sized material easily.