>>> I agree that weeds won't grow in it. I don't have to weed the areas I haven't cultivated.
Weeds won't sprout
from seed below 15cm (and actually more like 3 -10cm). But weed seed near the surface will sprout.
>>>>all angular rock, 2-8cm, with just enough soil to fill the open spaces created by the rock.
Almost a perfect description of the "soil" on the house pad where I have been working to create a rose garden ... Whistling
That's exactly what he discovered: it's not important for his cold hardy cactus to have lean soil, just very good drainage (and warmish soil).
>>>The reason I like the granite is I was told the plants do get some mineral nutrients from it. What is your thoughts on that?
Definitely. In days gone by, gardeners knew this, too. It was normal for miners to periodically bring home rock dust to spread in their vegetable gardens.
Minerals from rock aren't as readily available as the soluble nutrients that we normally think of (NPK). For rock, more surface area means more mineral availability, and the smaller the particle, the more surface area. When I buy 50 pound bags of granite grit, there is always dusty small particles that settle at the bottom. For the grit I use as a surface dressing in pots or troughs, I sometimes sift out these smaller particles, too. But I always save all this to mix in the soil in pots or in the open garden. I am not sure what all the usable minerals are that are available granites or other rocks. Lori (
@growitall ) would know.
