Omitting bark from gritty mix

fortyonenorth(6b)January 15, 2013

I'm sure this has been asked previously, but I'm wondering about the merits of omitting bark fines from the gritty mix and using a 1:1 mix of granite and Turface. Al, I've read posts where you have said the PBFs are an economical way to "extend" the mix. I understand that, but it's the one thing that's really inconvenient for me to get "right" - especially this time of year when I can't chip/shred bagged PB mulch. My application is specific to succulents, but I'm interested in using it on other, non-succulent, plants as well.

Thank you for reporting this comment. Undo
tapla (mid-MI z5b-6a)

An appropriate size bark makes a small measure of nutrients available as the bark breaks down, and makes the soil less expensive on a per volume basis. Both are minor attributes a grower can do w/o.

I think that if you eliminate the bark, you'll need to change the 1:1 ratio of granite:Turface to something like 3:2 or 2:1 in favor of the granite. The reason is, the granite and bark combined make up the largest fraction of the soil, and those components are both larger than Turface. Even screened Turface is small enough to support about an inch of perched water. The Turface will tend to filter in between the grit particles and make for fewer large pores than if there was a suitable size bark in the soil. It's nothing that can't be worked around with a minor adjustment.


    Bookmark   January 15, 2013 at 4:24PM
Thank you for reporting this comment. Undo
nil13(z21 L.A., CA (Mt. Washington))

If you omit the bark you are basically using the Missouri Gravel Bed formula of pea gravel and calcined clay. They found that somewhere about 30-40% fraction of calcined clay maximizes water retention without impacting aeration. I use 2:1 ratio of pea gravel to turface. I keep all kinds of things in that mix. The succulents seem to like it.

    Bookmark   January 15, 2013 at 8:24PM
Thank you for reporting this comment. Undo

Thanks for the replies. Al, good points, as always. Nil, I had never heard of the MGB but, yes, it seems similar to the granite/Turface, only scaled to nursery production. Interesting stuff!

    Bookmark   January 15, 2013 at 9:25PM
Sign Up to comment
More Discussions
"tapla" root pruning question
Hi Al, I bought another Brush Cherry, and wanted your...
Root bound jasmine separation
HI.. It is a first time I disturbed a rootball of...
Al's Gritty Mix -- A Learning Experinece
I came to this forum a few weeks ago in an attempt...
Indoor vegetables and 5-1-1
I'm growing vegetables indoors in containers. Is the...
Lateral water movement in 511 mix under drip irrigation
I would appreciate it if someone can give me an indication...
Jacques (MP, South Africa) S
Sponsored Products
Tara Convertible Mini Chandelier by Kichler
$327.80 | Lumens
Philips Pendant Lights Wave 4-Light Chrome Hanging Pendant 375001148
Home Depot
Philips Pendant Lights Channel 72-Light Satin Nickel LED Hanging Pendant
Home Depot
Thai Bed
| Italy Design
Philips Pendant Lights Cosmos 1-Light Satin Nickel Hanging Pendant with Clear
Home Depot
Philips Pendant Lights Mojave 1-Light Satin Nickel LED Hanging Pendant FA0073836
Home Depot
Philips Pendant Lights Mojave 1-Light Satin Nickel LED Hanging Pendant FA0012836
Home Depot
Philips Pendant Lights Mojave 1-Light Satin Nickel Hanging Pendant FC0020836
Home Depot
People viewed this after searching for:
© 2015 Houzz Inc. Houzz® The new way to design your home™