Coir is excellent, it makes a great medium. No need to check out of date sources. Most pot growers use it all the time. Someone is really out of touch. Remember anybody can post in these forums. The coir of old is nothing like the present product. I would not go higher than 25% compost, I myself would use 1 part compost, 2 parts coir, 1 part bark, and 1 part perlite. I would add micro nutrients, beneficial fungi and bacteria. I would use all products mentioned as compost, a mix of them, Manure and leaf compost as the base, add small amounts of worm casting(this is a great product!) and guano. The beneficial bacteria and fungi are not essential, but I have found they tend to help if any problems arise, and kick start the plant. I like Mycogrow, and Biota Max. I make a solution of both together, and dip plants in it before planting. But any method of application is fine. Use left over product as a drench or foliar spray for all your plants in ground, in the house etc. http://www.fungi.com/product-detail/product/mycogrow-soluble-1-oz.html http://biotamax.com/ORDER.html

Al, I've appreciated the thoughtfulness and vigor with which you approach your subject and have learned a lot from you while browsing these forums. I have around 300 plants in containers, in and outdoors, orchids, ferns, common junk stuff, lots of epiphytes on wood, begonias, vegetables, maples, succulents, cacti, etc. I haven't given them a lick of inorganic fertilizer in three years and would agree that the results can be mixed. Lately I've been brewing my own actively aerated compost tea using homemade worm compost, kelp emulsion, a handful of good garden soil, and a few other organic additives in small amounts. This mixture is aerated and vortexed for 18-24hrs during which time the microbial populations multiply, making a rich actively biological soup. I use this regularly on all my plants, and fertilize between compost tea applications with organic seaweed or fish emulsion type fertilizers. I also keep a small anaerobic compost tea brewing and I'll use small amounts of this every month or so. Since I've started using the compost tea my plants have all seen a remarkable uptick in both foliar growth, blooming, and just general "health" as compared to just organic fertilizers. My take on it is that the compost tea supplies a steady stream of microbes that the plants can symbiotically partner with to convert the organics into usable nutrients. I totally agree that good drainage is key and if the soil is too heavy the compost tea can quickly turn anaerobic in the pot and result in all sorts of problems. A fast draining mix combined with regular compost tea applications and organic fertilizers seem to have a lot of advantages and to keep my plants reasonably healthy. I can't tell you exactly what proportion of NPK the plants are getting, instead I rely on an entire ecosytem with all of its sloppy redundancies to allow the plants to orchestrate their ancient microbial dance and get what they need. I understand that chemical fertilizers work, it's just the widespread and longterm impacts that these substances have on the larger ecosystem (gulf dead zone, algal blooms, groundwater nitrification, etc) that makes me want to avoid them, even for container culture. Nurseries are large contributors in this nutrient-pollution overload, but if you add up all small-scale homegrowers who put miracle-gro on their tomatoes it equals a whole lot of nutrients that are being converted from fossil fuels and released into our larger environment. Historically nitrogen has been a severely limited nutrient on the earth, thus the biosphere's incredibly tight hold on it via the humus and soil building processes. I totally respect that you seem to be solely interested in what's best for the plant when it comes to container culture, and I agree that inorganic fertilizer do yield amazing results. But I believe we need to think beyond the individual plant, to the ecosystem in the pot, and then to our wider community or plants animals and humans that we share our planet with. We can (we have the choice!) develop new technologies and techniques that allow us to avoid the use of chemical fertilizers that imbalance our environment and tax our natural resources and instead rely on the built-in recycling and life-support systems of the greatest systems engineer imaginable, mother nature.

I would ordinarily suggest you not put any compost in your mix, but since you're going organic I would go for a 3 part coir + 1 part organic compost mix + 1 part perlite (vermiculite would be marginally better, but since you have perlite it's not a big deal) for a 60/20/20 mix overall (by volume, not weight). Watch your watering, both over and under watering...and mix the container mix very well before putting it into containers. Soil + soiless container mixes are a bit more tricky to monitor than a total soiless container mix. This isn't a "slam dunk" mix...it's just what I would do if I had your materials and I was planning on growing them with organic methods. Ordinarily I wouldn't put compost anywhere near a container mix, much less 20%, but without chemical fertilizers the nutrient leeching vs availability can get a little harsh and the organic fraction will help hold a bit of it around in the root zone a little longer. I would also err on the side of "too little" compost in that mix over "too much" if you're measuring out the parts by sight.

I like adding fungi, it's cheap enough, some think a waste, but I think it works. I would prefer pine fines in the mix too. It helps reduce pathogen growth, makes the mix drain well and also resists breakdown, it lasts awhile. And to me peat is a much better product. Most studies show better growth in peat than coir. I'll use coir when all the peat is gone. Most here do not like adding compost, but it works so well and prevents root rot. I always use it. You live in a pretty hot zone. So this mix might work really well for you. It should stay quite moist. If you want to try fungi (depends what you are growing, 90% of plants benefit from mycorrhizae fungi.) Mycogrow sells a decent mix for 6 bucks. Here is a link that might be useful: Myco grow This post was edited by Drew51 on Sat, Dec 20, 14 at 1:43