2 Dry Quarts Black 1/4 inch Bonsai Lava Rock


Horticultural Lava Rock

Size: ¼ Inch

Condition: Sifted, Washed, Dried and Bagged.

1/4 inch Lava Rock are used for the vast majority of fast draining soils and is our number one seller. This includes cacti and succulents. We offer Black and Maroon (red). Available in Quart, Gallon, 2 Gallon and 3.5 Gallon bags.

Lava Rock is used as a soil additive or top dressing in the art of bonsai. Mix with other ingredients such as pine bark fines, granite grit, calcined clay, and or dirt to create a succulent, cactus or bonsai soil specific to your needs.

Features include…

  • Manufactured in the US.
  • Consistent sizes, ready to use, no sifting required.
  • Pure lava rock, no fillers, no chemicals or artificial coloring.
  • Multiple bag sizes and colors to best fit your potting needs.
  • Packaging. Our aggregates are professionally packaged in custom 6 mil bags.

Did you know?
All of our soil products are state inspected and tested on a regular basis in order to comply with multi-state regulations.
This ensures you receive material free of dangerous pathogens that can damage or kill plants. This is also required to maintain six nursery stamps that allow us to ship to all 50 states.

Click the Additional Information tab for more details.


SKU: 723905647407 Categories: ,

Additional information

Weight 3 lbs
Dimensions 6 × 8 × 4 in

Jet black when wet. Black with a hint of ash when dry. Natural color. No dyes.

Raw Material

Volcanic rock.

Country of Origin(COO)

United States

Average Particle Size

1/4 Inch

Minimum Particle Size

1/8th Inch

Maximum Particle Size

3/8ths Inch


2, Dry

Cubic Inches


Cubic Feet



2 Quart Bag


9.94 … Contrary to popular belief, lava rock is not pH neutral.

Plant Type

Soil Conditioner


Dye-free. Chemical free

Other Applications

Aquarium gravel, ash trays, top dressing for plants, fire media, garden soil amendment and fire pits.

Bulk Density

.470 ounces per cubic inch

Conversations ...

  1. Question

    Jacob covert (verified owner)

    Is this okay to add to the premixed bonsai Jack succulent soil? If so, how much would you recommend I add? Or should I only use it as top dressing for my succulents? I love the lava rock and I love the succulent soil but I’d really like to mix the two to save on having to buy soil so often. Thanks in advance!

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    • One person found this helpful

      Bonsai Jack

      Hello Jacob,

      Thanks for the message. We generally do not recommend adding ingredients to the mix because its optimized for succulents. Adding a little bit of lava would not hurt. Probably no more than 20 percent.

      Have a great week. Please call or email if you have questions or concerns.


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