Can perlite be eliminated altogether?
Hi. I have about 3/4 of a yard of double ground pine bark. It looks like it has a lot of very fine stuff in it. I tested the drainage of it by filling a 12 ounce plastic cup with a drain hole in the bottom, saturated it, and let it drain. After it finished draining naturally, I could only shake about 3 tablespoons of water out of it. This told me that the double ground bark drains well. I made a large batch of 511, and just assumed I could eliminate the peat, so I made a 5:1, bark-perlite batch. I'm not sure why I added the perlite if the bark alone drains well. I think I was just scared to leave it out. After that, I took a gallon of the plain double ground bark and sifted it with a kitchen strainer to see just how much fine stuff was actually in it. I got just about a quart of fine stuff out of the gallon, which would be 25% 'peat', a little more than Al's suggested amount of 1/6th to 1/7th of the whole for the 511. Since I'm a little nervous about too little water retension because my containers will be in full sun and drying quickly, and the bark alone drains well, can't I just eliminate the perlite also, and go with the straight double ground bark in the containers? Thanks. Ed.