This is why the ReptiBark is such a good bet for my application... because it breaks down less quickly, I can go 2 or 3 years without having to re-pot... or with adding a top-dressing only. I don't have to worry that the ReptiBark will decompose right away. I find that if I soak the ReptiBark overnight before using any in a mix, it's much less likely to become hydrophobic. Plus, my pots aren't drying out that quickly... they're indoor, out of direct sun and any wind, as opposed to outdoor containers and the conditions there. Honestly, I haven't had any issues with the small bags, as used for my own applications. When I know a pot will spend time outdoors, I use a different bark in a medium closer to the 511. I found a few bags of some pine mulch at Lowe's or somewhere like that... no idea on brand names or anything... but it appeared a little darker in color, smaller in size, and perfect for using in a 511 type mix. This past spring, we actually added a bunch of composted wood chip mulch to our raised beds and even turned a bunch into the garden for aeration and whatnot... so far, so good! The basic concept is working well for us!

I thought I posted this on the gardenweb forum. Now it's houzz? Had to sign up for a new user name. Anyway soo - you can get the Naked Gardener Compost or Debco Premium Potting Mix from Masters (closing soon). Course Perlite is from The Perlite & Vermiculite Factory Myaree (much cheaper than anywhere else). Sand I got from a bulk landscape place (lawn mix) but you can get 10 or 20kg bags of builders sand at Bunnings. Zeochlor is in the pool section at Bunnings. Rock Dust I got from the manufacturer direct somewhere in Bibralake (called Natural PK) but I think but you can now get a similar product from Waldecks (in Myaree at least). Waldecks also sell bentonite clay. I still want to try the gritty mix but getting my hands on all the materials has proved very difficult when I tried last year. I found a Queensland company that makes course DE (for mopping up oil/chemicals) but they didn't have a distributor in Perth. Nobody I could find has pine bark in the right size - and even if they did I'd have to by a cement mixer and modify it with a fine wire to screen it. Honestly, if an agricultural company were to produce the gritty mix and sell it in bags I think they'd make bank - even considering how long it lasts.

I've never grown them in an orchid mix, or seen them grown in such, but that doesn't mean it won't work. They can easily be grown in either the gritty mix or the 5:1:1 mix. It's easy to overlook the fact that plants in containers may very well not prefer the same type of root medium in which they grow in situ. As long as you provide a medium that holds little or no perched water, you water/fertilize appropriately, and give the plant the light/temperature it prefers, you'll be fine. The key to providing a healthy root medium lies not so much in what materials the soil is made of; rather, in the size and uniformity of the particles that make up the medium. The potential for your plant to prosper is much greater in a soil that has a favorable structure and no organic fraction than it is in a soil with a significant organic fraction but with an unfavorable structure. Al

Yes you can, and in the short run 5-1-1 in may actually perfom better than the Gritty mix. But it will wear out quicker (break down) than the gritty mix. I tend to think of annuals going in the 5-1-1 mix, and perinnials in gritty mix. If you are going to be up-potting in a couple of years go with what you have. Either are a better choice than most anything you can find in most garden centers. Gritty mix makes future repots a dream, tip the pot over and you have bare roots.. Grading the pine bark is not fun, I hate it! A major concept of the gritty mix is based on particle size, larger particles have less surface area (by volume) and thus less water retention. 1/4 to 1/8 inch seems to be the optimal size, although due the screening process of pine bark and the thin strips I will let most 1/2 and under get in the mix (under 1/8 is not good either). If you are looking for Turface MVP check a local irrigation supply house, the stuff was designed for baseball diamonds so look in that direction. The dust is not good for the mix (particle size) The gran-i-grit is intended for chickens to help them digest grains. There are many other products other than gran-i-grit that will perform just as well. Look to a local farm supply house for the rock. Rock dust is not good for the mix (particle size) Gypsum is available at the big box home improvements stores. Gritty does dry out quicker than potting soil so you do need to water a bit more often. It is extremely difficult to overwater with gritty mix, that includes mother nature overwatering. Root rot is probably the number one killer of potted plants. After water, air is the most important thing you can give roots (most plants), more important than fertilizer. Gritty mix excels at this without drying out the root system. Gritty mix is heavy stuff, an advantage of heavy is the pot is less likely to tip from heavy winds. Al is a smart guy, it is such a simple concept.