Allan Balliett wrote: > > I'm going a little nutty right now, trying to learn a jargon so I can > speak with people who are quite a drive from me and who really don't > have the time to spoon feed the ignorant. > > I'm looking to buy a few yards of 'crushed gravel sand' to use in a > potting mix formulation recommended by Heinz Grotzke in "Biodynamic > Greenhouse Management." > > So far, I've been offered trap dust and 1/4inch (and lower) stuff > from a realatively close-by quarry. If I can communicate screen size, > I think I can buy what I need. > > AND, I would assume that it's cool to take basalt instead of granite, eh? > > Which is to say that I've found a source for basalt trap dust down > here. My recollection is that it tests very highly on the Callahan > scale (paramagnetics), but I'll have to have it tested again. > > Thanks > > _Allan
Hi Allan I use a basalt rock dust in my potting mixes . i also add about 10% fine clay dust from my own subsoil. This brings in a bit more phosphate and the clay infuence to a potting mix . For sand i use about 10% any more then that and your seedling trays become too heavy to lift and carry. The best seed sowing/potting mix is made with leaf mould. Each year I make up a ix to be used the following year.To a collection of 60% softwood and 30% hard wood leaves mixed with seed free grass or a green crop. I add 10% fine sand 10% fine clay 10% chicken manure, 10% cow manure, alight sprinkling of lime.Prep500,502-508. Each time i turn the pile i add armfulls of comphrey and nettle, 20 litre bucket of worm castings from the worm farm to kick start the process and sprinkle a handful of Barrel Compost over the pile. I keep the heap covered with weedmat that allows rain through but keeps out the birds and prevents weed seed contamination. It also keeps the temperture more even and bring the worms evenly through the whole heap. this make a very good friable mix ready to use with out any screening except to cover the seeds.I also use this as apotting mix by adding some fish and seaweed meal about a month before use.All seedlings are then sprayed twice month with a foliar tea. At planting time all plants are dipped into Rooting Compound from Garuda Biodynamics to which i add worm pee. Cheers Tony Robinson Rambler Flowers NewZealand Cheers Tony