Pros and Cons: 1/4” vs 3/8” lava (scoria)

[Shinjuku]

I’m lucky in that I can get Dry Stall locally (1/4” pumice). Since it’s hot and dry where I live, I want to add in more lava (scoria) to my soil mix to help with more water retention. I know of two options for a source:

At the local rock yard, I can fill up a 3.5 gallon bucket with 3/8” lava for $3.50, so $1.00 a gallon. Alternatively, I can order 1/4” lava online (Bonsai Jack, American Bonsai, etc.) for around $9 - $10 a gallon, depending on quantity. Big cost difference.

What are the pros/cons of the smaller 1/4” lava vs the larger 3/8”?

 

[River's Edge]

I’m lucky in that I can get Dry Stall locally (1/4” pumice). Since it’s hot and dry where I live, I want to add in more lava (scoria) to my soil mix to help with more water retention. I know of two options for a source:

At the local rock yard, I can fill up a 3.5 gallon bucket with 3/8” lava for $3.50, so $1.00 a gallon. Alternatively, I can order 1/4” lava online (Bonsai Jack, American Bonsai, etc.) for around $9 - $10 a gallon, depending on quantity. Big cost difference.

What are the pros/cons of the smaller 1/4” lava vs the larger 3/8”?

Smaller size particles will retain more moisture, promote smaller finer roots. So it depends on which species you are working with and what your developmental goals are at the time you use it. I use finer grades of particle size for cuttings, seedlings and stock that i wish to develop finer root structure. Generally for most of the stock in my Nursery both in development and refinement stages i prefer 3/8 size. But i often use the smaller size for the top layer that gets changed more often.
To a certain extent it depends on what else you are adding to the mix. I try to keep the particle size pretty close to uniform for the various components.
If you adjust your watering and care practices to your soil mix then either can work.

 

[hemmy]

At the local rock yard, I can fill up a 3.5 gallon bucket with 3/8” lava for $3.50, so $1.00 a gallon. Alternatively, I can order 1/4” lava online

I’m sure you know, but I would have thought the local Sacramento bonsai nurseries would have scoria. I would have expected it to be between those prices you quoted. Also the GBSF Convention is end of the month, there might someone there with scoria or a scoria mix. You should also check the rock yard for size range. Sometimes a bulk aggregate will be sized at 3/8” Minus, meaning it has a range of smaller particles which you could sift.

 

[TN_Jim]

I’m lucky in that I can get Dry Stall locally (1/4” pumice). Since it’s hot and dry where I live, I want to add in more lava (scoria) to my soil mix to help with more water retention. I know of two options for a source:

At the local rock yard, I can fill up a 3.5 gallon bucket with 3/8” lava for $3.50, so $1.00 a gallon. Alternatively, I can order 1/4” lava online (Bonsai Jack, American Bonsai, etc.) for around $9 - $10 a gallon, depending on quantity. Big cost difference.

What are the pros/cons of the smaller 1/4” lava vs the larger 3/8”?

$1/gal..think I could make that work...even after fines and smaller grains sifted out

guess it depends on % of largest
gotta pic of a handful or such?

as riversedge touched on, there was a recent thread regarding homogeneous grain size you may want to consider

 

[Bananaman]

I’m lucky in that I can get Dry Stall locally (1/4” pumice). Since it’s hot and dry where I live, I want to add in more lava (scoria) to my soil mix to help with more water retention. I know of two options for a source:

At the local rock yard, I can fill up a 3.5 gallon bucket with 3/8” lava for $3.50, so $1.00 a gallon. Alternatively, I can order 1/4” lava online (Bonsai Jack, American Bonsai, etc.) for around $9 - $10 a gallon, depending on quantity. Big cost difference.

What are the pros/cons of the smaller 1/4” lava vs the larger 3/8”?

Just go to Maruyama nursery. They have big piles of 1/8 and 1/4 inch scoria as well as a pile of 1/4 mocha lava. You can use that straight away. All 5.00 a bucket.

Thats a shot thru the fence and some buckets I got as well as a close up of the stuff
Good luck

 

[Bananaman]

Maruyama Bonsai Nursery
1423 47th Avenue
Sacramento, CA 95822
(916) 421-6888
yuzomaruyama at aol dot com

Hours
Monday - Saturday: 8:30 - 12:00

 

[bonsaidave]

Dang what a sweet deal. Nothing like that around my area.

 

[herzausstahl]

Maruyama Bonsai Nursery
1423 47th Avenue
Sacramento, CA 95822
(916) 421-6888
yuzomaruyama at aol dot com

Hours
Monday - Saturday: 8:30 - 12:00

Boy do I wish we had that here! Lol