Hi - Too many of the articles we read are written about e.g. Junipers growing outdoors in Dakota or somewhere completely irrelevant to tropical houseplants (even ones we put out for the summer), so it's important to know the source of the info if possible and relate it to our conditions. If I were you I'd break the bark up into small pieces if possible, use either the grit or turface but not both, and add that 1/3 (or 1/4 if you like) of potting soil with a fair amount of perlite in it, but try to stay away from peat based ones, though it's pretty hard. An orchid mix, rather than cactus is also a pretty good alternative, though some tend to have large stones vs small gravel, not really suitable for a small Ficus. I do think that with the new mix you need to gauge watering by need rather than any kind of schedule, esp. taking into acct. how many hours of what kind of light the tree will get. I tend to think your every 2-3 day sched. might be too often for the tree, but others will disagree. It's all a mystery until it isn't, but trial and error is how you learn.

I agree with moochinka, I agree with others I've heard, I'm amazed at the many variations I've heard on the theme, lol. I've tried different things also, and nothing has hurt my bonsai. Our circumstances are similar, mdbonsai, so I will relate to you what I'm happy with for my tropical bonsai. They are under grow lights 7 months, outside 5(ish).

The smallest granite chicken grit, which is labeled as #1, and pine bark fines which I buy under the label Soil Pep, and mixed in equal proportions. I fertilize them, dousing the roots and leaves completely, with Bonsai Pro at each watering.

Every plant has unique circumstances so I evaluate each for watering individually, but to generalize a little, most of my plants need watering in the 2-3 day range in 90F-ish (common in Summer here) weather, though my 1-inch deep pots need it every day.What I see with this at repotting time is a very dense network of fine feeder roots, which is what I'm looking for.

I tried the larger grit, #2, but found that on the hottest days some of my plants needed watering twice/day. I work 12-hr shifts, so that's not a good option for me. I could have added another water-retentive component, say turface or pumice, but I went the smaller grit route and it worked out fine. Keeps it very simple, which I like.

ez

I would seriously NOT recommend anyone to use bark (or any other) 'Fines' - that's the part we dump after sifting, not the part we keep. It clogs the soil and roots and I imagine it's only your grit mix that otherwise has let you get away with it, but it's a bad idea.

Good results are hardly a bad idea. Individual components are always there to balance other components and make a good (hopefully) whole. It's the case with every successful mix, I'm just describing one that works.

ez

addendum: I wonder, are our definitions for pine bark fines the same? I buy pine bark sifted to a quarter-inch for my succulents and cactus. Soil Pep is smaller than that. I would consider it very similar in size to this picture from New England Bonsai Gardens.

ez

Thank you both for the help :)

I went with 1/3 each of fir mulch, chicken grit (quartz), and Turface MVP with a touch less of the latter. I screened everything between 3/32 and 3/16, with nothing that wouldn't slide through the 1/4 in screen. I bought a 9 dollar 6in nursery ficus b that I separated into 3 containers (three diff trunks), so while I really want them to thrive, at 3 bucks a piece the cost isn't huge, and I can learn via experience.

Cheers,

MD

PS, screening the mulch was the least fun part :(

Looks like you're off to a good start. Enjoy!

ez

MD - You've been reading up on the gritty mix, and it will serve you well. The reason you use Turface AND grit in the same mix is because it allows you to adjust the amount of water retention. By keeping the bark fraction at no more than 1/3 of the mix, you ensure the soil cannot collapse as the bark decomposes. by altering the ratio of Turface:grit, you control water retention. For example, 4 parts of screened Turface, 2 parts of grower or #2 cherrystone grit, and 3 parts of screened bark yields a soil with much more water retention than the 1:1:1 mix w/hardly any sacrifice in aeration or drainage. For less water retention, you might use 4 grit, 2 Turface, and 3 bark.

FWIW, it doesn't make sense to pay the long dollar for the ingredients and then not take advantage of what they have to offer. The gritty mix, properly made, holds water only on the surface of particles, inside of particles, and at the interface where particles contact each other. There should be no water in the spaces between particles. When the pores between soil particles are filled with water, it inhibits water/nutrient uptake, which is an energy-driven process that must take place in the presence of oxygen. Adding fine material that clogs these large pores ensures they will be filled with water after a proper watering, which undoes any potential advantage the soil has to offer.

Bark fines contain material from dust size up to 1/2" or larger. The material we want in our soils varies by type of bark. For pine bark, 1/8-3/8 is ideal. For fir bark, 1/8-1/4 is ideal. Particle size is very important if you wish to get the most from your soils.

Al

Ha! Thank you, Al. I have indeed been reading up...I think I have read the majority of your posts-debates included-on soil, watering, and fertilizing on multiple forums. I may have even read all 18 maxed threads on soil. For me, the information you and others have provided has been more than informative, it has been tremendously enjoyable. My passion is reading and learning, so I have really enjoyed immersing myself for hours in the world of soil composition and so forth. So, thank you again.

I laughed about your comment on cost. I paid 2.50 for 5lbs of quartz poultry grit, 6.00 for filling my own big garbage bag of fir mulch, 15 for the turface, and 16.00 for my drive-through lunch of 2 burgers & onion rings--the lunch cost the most, and at least I still have soil ingredients to use in the future.

I briefly considered rebranding the reddish poultry grit as "decorative rock" and selling it for 10 dollars a pound...as I have seen it sold.

Best,

md

Ah ha! I've been tossing the "why" of the 4-2-3 ratio around in my head and finally realized that it equals 9 parts of which the bark is 1/3 of to prevent soil collapse. I assume the collapse would be due to the breakdown of the bark over a period of years, though. I'm slow, but glad I think I've determined the reason for that particular ratio for increased water retention.

Bingo. ;-)

Al