Hello, I've been pondering over an idea I've had for some time now, but don't know if I SHOULD do this or not.
The idea is that because I garden on heavy clay soild and I'd like some plants that need fast(er) drainage such as Eremurus and Agapanthus, I'd dig out new beds two feet deep or so. But instead of relying and trying on amending the native clay with compost (or perhaps maybe the bottom), I'd just get rid of it altogether, leaving me with a wide bed (hole) like when you're digging a pond. Then backfill with topsoil (not completely sand) and compost.
I know people talk of adding grit/sand to a planting hole is bad because it acts like a sump, but done on a larger scale (several m²) will or won't this work?
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