Rich
Yes, you're right, the DG will give you better mineralization than the chips. Most DG comes as you describe, with all the dust and fines from the completely broken down granite as well as the chunks that we like to use. This is fine for pathways and other hardscape because it 'anchors' nicely. Rather than sift DG, I just wash it. It quickly removes the mud and fines. You can do this most efficiently over 1/4 inch hardware cloth or other screen, or simply using a 5 gallon bucket tilted while running the hose in the bottom of the DG. You can then grade the larger pieces or use it as is. I use it for bonsai ground cover, it is much more attractive than chips or pumice. It has a more natural look.
Brent
EvergreenGardenworks.com
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