I'm trying to understand why perlite gets a bad rep? It's recycled..Probably hydrocarbons. I noticed people steering clear of certain amendments and even having things shipped when they can get something of the same elemental value up the street..
..Alfalfa/Neem
Lime/Oyster Shell flour
Bone meal/Crab meal
You bring up a good point in your last paragraph. Something I failed to point out. I would never (personally) exceed 8-10% bio char in my mixes as bio char is very Alkaline in nature. I'd personally like it around 5% of the aeration percentage. This doesn't seem like a lot to someone who hasn't observed what 5% chunky bio char can do
Great carbon builder.
Think back. We've both been here for years and have seen it happen. The main influence being Coot/Lumperdawgz and the whole *new* no till method. People, especially the inexperienced, took everything at face value despite experience and observation to the contrary because Coot said so. Most of it works very well. Some, not so much.
Most of these 'designer' amendments are off the shelf items on the west coast, especially in the PNW and would naturally get used. I would also. But the stuff 'up the street' never got mentioned and it was felt that one must have oyster shell flour instead of Ag lime, fish bone meal/crab meal instead of steamed bone meal and so on.
The cost in shipping was enormous, but essential for no till because Coot said so. Never mind that the 'up the street' stuff worked just as well for way cheaper. Neem was an exception since there is nothing else much like it.
I still love neem cake/meal, but have gotten much less generous in its use. Another gardener summed it up quite well, "A large bag of kelp and a small bag of neem". The alfalfa and soy meals are seeing much more use again.
Got into huge arguments over at GC when I called BS on Coot's claim that perlite would float to the surface even from the bottom of a huge container. From experience with my own nursery I knew this wasn't true. Others, with experience, like yourself, agreed. The ones with no actual growing experience were the ones insisting this must be so, since you know who stated it. Ignorance can get really tiresome. LOL
Perlite is an inert mineral with a water content that, when heated, makes like a rice krispy. That's pretty much it, no recycling or hydrocarbons involved. No, it doesn't cause cancer, but the dust IS an irritant as is the dust in a grain silo.
It is also used as insulation in CBS construction and I'm not 100% on this, but more than likely its first use before the nursery industry discovered it for aeration purposes. Vermiculite is used similary for insulation, but I don't use it in my mixes because it retains too much water. Seems to work ok in some seed starting mixes though.
