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 use both mixes, for indoor and outdoor plants, and generally speaking, I use 5-1-1 for plants that need more water, as that's the recommendation from Al. However, I can't say I've noticed much difference between the 2 for how long plants go between watering. I don't think indoor or outdoor use makes much difference, although 5-1-1 might break down quicker, as mostly bark. However, you can combat that by using larger particle bark. I use propagating bark by Melcourt for gritty mix, but usually, either potting bark or their Sylvan Premium Pine Mini Mulch (think that's what it's called) for 5-1-1, as those are larger particle and seems to work better for that. I also use 5-1-1 to save money, for shorter lived plants, btw, as bark is still the cheapest of the ingredients here. I would probably use either for plants you mentioned, but might tend to 5-1-1 for fiddle leaf. I wouldn't worry about over-watering for either mix: you will be very hard-pressed to over-water anything in either, I've found. Evergreen plants, such as ficus, need re-potting in stages, as they're evergreen, so you can't bare-root them. Al describes the procedure in various places on here. Basically, you remove pie-shaped wedges of the potting soil, and fill those up with your chosen mix. I think Al said to remove about 1/3rd to 1/2 of total soil volume with each re-potting. Then next time, you remove the opposite wedges, so within 2-3 re-pottings, you will have them in fully in new mix. I've had good success with this method, for plants that were previously in normal soil, including ficus. At first, I was a bit worried about how the different types of soil would affect watering, so that the potting soil would stay far wetter, but if they do, it does not seem to harm the plants. Al says that it does not matter, as the extra water is drained out of the potting soil by the gritty mix or 5-1-1. You can also prune the roots in the wedges, or if you don't, you can use chop sticks or similar to get the mix in amongst the roots. As for time of re-potting, it's far more crucial for outdoor plants, than for indoor plants, advice is to re-pot after a growth spurt, I think. But I've re-potted indoor plants at all seasons, and not had any problems... Hope that helps - am no expert by far, either. But have found, since I've started using these mixes, it's hard to do anything much wrong - plants just thrive. Keeping up with watering is my biggest problem now.

Hi everyone. John - You say, " I have a dozen or so bromeliads that I've mounted on trees, of course no organic matter there, and they seem to be doing well." Mounting brom's on trees is just growing them naturally as they once grew in habitat; you say "of course no organic matter", what about the bits of fallen leaves, dead insects and bird and small animal droppings caught up in the roots and in the central vase where they are mixed with water to form a weak liquid fertiliser? These are all organic and are nature's continuing supply of dilute fertiliser. You say, "I'm wondering why ephipytes would need organic matter in their pots"; the answer to this is that when man/woman originally took plants from trees and started growing them in pots because it was more convenient, the roots were no longer able to roam where ever they wanted in search of sufficient nutrients and were from that point on confined within the pot and wholly reliant of the grower to provide the required nutrients either in the potting mix or via a foliar fertiliser. Whether these nutrients are best if man-made or natural is an ongoing argument, however "organic" is what nature originally intended and provided, and as the plants no longer have access to the natural fertiliser provided by Mother Nature, it has to be substituted with some other type of food and organic is the closest thing to natural that's available. I love your arrangement, but I don't envy you trying to move it into your house. All the best, Nev.

Soil Fertility Some Average Values and misc PPM based on the dry weight of the loam soil Sp=1.42 (Sp=1 is about 62.4lb/cuft or 1000grams/Liter(1000 cubic cm ). Low- N: 0-20, P: 0-12, K: 0-50 Med- N: 20-50, P: 12-25,K : 50-100 High- N: above 50, P: over 25, K : over 100 Note: Actual amounts of the nutrient is based the reference used for the PPM calculations. Example the 100ppm in a water solution is less than 100ppm in loam soil. The loam amount is 1.42 times more than the water. “Sp” is the ratio of the weight of an equal volumes of a substance compared to water. Sp Water 1.0, Sandy Loam 1.47, Loam 1.42, UC Mix Potting Soil 0.24, and PeatMoss 0.1 Misc Note: On a Fertilizer Bag the middle number is the percentage per weight of P2O5 in the fertilizer. The actual P amount is about 0.437 this value. This was calculated from a periodic table using the atomic weights of Phosphorus and Oxygen. The Phosphorous being about 43.7% of the total weight of the compound. The same for K2O, K is about 83% of the total compound weight. Example 100ppm Nitrogen in water is 100 mg N per Liter, but 147 mg N in a liter of Sandy Loam soil. For water 1ppm is a 1mg/Liter. Correction on the Previous MG Potting Soil Calculation: Bag Label Info 2.25cuft (63.71 liters) net weight 29.25lbs (13.26 kg) Density 13.26/63.71= 0.208g/ml or cubic cm Sp is approx 0.21 Nutrients N 0.21% P2O5 0.11% K2O 0.16% 6 month release Total Nitrogen in a liter mix is 1000grams *Sp mix*.21%N= 1000*0.21*(0.21/100)= 0.441grams N per Liter ( 441ppm N total, 73.5ppm monthly@ Sp1 reference) Duplicating using 6mo Osmocote Plus 15% N is 0.441 g/0.15= 2.94g/Liter approx heaping 1/2tsp. Just under the 1TBS CRF per Gallon of Mix recommended in Gritty Mix Recipe.