3.5 Gallons 1/4 inch Bonsai Block (14 Dry Quarts)

U$D 32.65

Bonsai Block

Size: ¼ Inch

Condition: Sifted, Washed, Dried and Bagged.


Bonsai Block is a lightweight high fired soil amendment with a variety of earth-tones including peach, ash, black, tan and dark grey. It can be used as a substitute for lava, pumice and hard Akadama.

Perfect for amending soil for all plant types including cactus, succulent, bonsai , orchids and other plants that require a fast draining soil.

It arrives prescreened, sifted and neatly packaged in several bag sizes.

Consistent ¼ inch particle size. This increases drainage and air exchange within the potted plant.

Cosmetics. Bonsai Block is a great looking aggregate. It has a natural pebble look with multiple earth tones. Works great as a top dressing.

Fired at extremely high temperatures. This helps prevent breakdown and ensures a long service life.

Bonsai Block is a superior product and is priced lower than lava and about the same as Turface. It has many of the same properties of Maroon Lava.

Please visit our blog for more technical details on Bonsai Block.


Click the Additional Information tab for more details.


GTIN 00857206008398 SKU: 857206008398 Category:

Additional information

Weight 19 lbs
Dimensions 10 × 20 × 5 in

uniform mix of earth tones

Raw Material

Calcined Clay

Country of Origin(COO)

United States

Average Particle Size

1/4 Inch

Minimum Particle Size

1/8th Inch

Maximum Particle Size

3/8ths Inch


3.5, Dry

Cubic Inches


Cubic Feet



One 3.5 Gallon Bag



Plant Type

Succulent, cactus, bonsai, orchid and other plants that prefer a fast draining soil amendment.


No dyes or chemicals.

Other Applications

Top dressing. An excellent replacement for Akadama.

Bulk Density

.403 ounces per cubic inch

Conversations ...

  1. Dori Decker

    Bonsai Block (1/4 calcined clay) pH 8.9 vs. Monto Clay (1/4 Turface) pH 5.6.

    I’m using your Gritty Mix #111 for my succulents and cacti, but I want to add something to my regular ole’ potting soil for my tropical plants to help increase drainage. Would you please tell me which of the two products mentioned above you think would work best for my purpose?
    Thank you.

    (0) (0)

    Something wrong with this post? Thanks for letting us know. If you can point us in the right direction...

    • Bonsai Jack

      Hello Dori. Thanks for the message. Both of them are calcined clay and will work fine. Monto Clay is an acidifier and Bonsai Block is slightly alkaline. If you are unsure of which one you need it would be a good idea to stick with the Monto Clay.

      Talk soon


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      Something wrong with this post? Thanks for letting us know. If you can point us in the right direction...




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