Volcanic cinders for pot palm planting?

[cagary]

Does any one know of a California source of small volcanic rock (cinders) for use in potting up palms into larger pots? Or do I have to stick with perlite and pumice?

There is a source in Hawaii, but the shipping is costly.

Thanks!

[Bruce in San Diego]

Hi,

Try KRC in San Diego.

[Matt in SD]

Hansen aggregates/A1 soils sells "scoria" which is black cinder.  I use it in my mixes.  It's ~$50 per cubic yard, or you can buy a 2-3 cubic foot bag for ~$7.  They are just north of Miramar rd, a few blocks east of the 805.

Matt

[Phil]

Cagary,

Matt is right that Hansen Aggregates sells scoria.  But, be careful in using it.  As an additive, either scoria or pumice is good for potting soil for palms.  However, one might think they should make a soil where the majority of its components is scoria or crushed lava.  In So Cal, this would be a mistake.  It gives a mix that is too "open" and dries out quickly with our dry weather.  Growers in HI use a lot of crushed lava because that's what they have available.  In HI they typically combine the lava rock with some peat moss.  This is also done so plants can be shipped to the mainland easily.  When such plants arrive in California, they should be repotted into a mix better for us and our weather.  A Hawaiian import typically and eventually goes on decline if the mix is not addressed.  The reason I mention the above is because of the question you posed.  Best regards,

Phil

[LJG]

Phil,

What about someone that sells a good limestone mix or just crushed limestone? I have some Cuban palms I need to pot up and want to make sure the soil is similar. Something better then the stuff usually mixed with peat to balance it.

[Phil]

Len,

I don't know much about crushed lava.  When I use pumice, there are always fines in it.  It's been no problem.  But, pumice is usually considered more of a physical additive to the soil as opposed to a nutritional one.

Phil