Notes: I sifted all three through the same 1/4-inch screen, using only the retained fraction.
by xj305ah
Notes: I sifted all three through the same 1/4-inch screen, using only the retained fraction.
by xj305ah
3 Comments
I’ve been asked a few times what is my substrate. I use 100% pumice. I sift the pumice through a series of sieves. The 1/8 inch and larger fraction I use for most Haworthia. The 1/10-1/8 inch fraction I use for Haworthiopsis, Tulista, and Astroloba. The 1/16-1/0 inch fraction I use for leaf props, rerooting, and sowing seeds. I discard anything that passes through the finest screen.
I have purchased lots of pumice over the years, and have found that most horticultural pumice floats. To me, it doesn’t retain water long enough to use as pure substrate. I lost a few Haworthia due to underwatering using this kind of pumice.
Some pumice sinks, it retains water longer than the floating pumice. I find it far better for my plants in my growing conditions (outdoors in San Diego).
There was a time when I had to repot 60-70 of my plants from horticultural (i.e. floating-type) pumice to the “better” pumice. I’ve learned my lesson.
I previously used General Pumice Products. It is a great product: pre-sifted and sized, and washed. But it is very expensive. Prohibitively so for large collections.
I now use Dry Stall. I get from my local Hay and Grain store. It is primarily sold for horse stall “bedding.” I sift and wash it myself.
Note: there is a product called Stall Dry, also sold at Hay and Grain stores. This is not pumice. Don’t confuse the two!
Hahah so the “shitty” pumice works better, good to know. Typically if it sinks after just a short time in water, it’s not going to meet “horticultural grade,” because it’s considered too dense. The light airy stuff that floats and only sinks after a long time of being waterlogged has usually been considered the good stuff. That’s why the shitty stuff is sold for cheap as horse bedding.
Good post breaking this down. This is what I buy here in the PNW – 1 cu ft is $8 bucks. It sinks, and works brilliantly for haworthia, gasteria, and cacti.
https://preview.redd.it/mwv2l8571m9d1.jpeg?width=3024&format=pjpg&auto=webp&s=12664f173e3fb83b41591818760e0e6492fc40aa