Soil for native plantings
I am helping a friend do a native garden in a front yard with "soil" that comprises yellow builders' sand mixed up with some grey soil and small bits of rubble and
cement (not massive amounts of the rubble, fortunately - most of it is small and bitty).
This crappy surface "soil" goes quite deep - about 20-30cm. So, it's obviously necessary to prepare the planting holes for the natives well, and here I come to my problem.
I would usually mix about 30-40% Bailey's soil conditioner with the local soil, along with a bit of sheep manure and a light sprinkling of water crystals. However, in this case I'm concerned that even top quality soil conditioner may not dilute this yellow sand stuff sufficiently to create a healthy soil environment for the natives.
Does anyone know whether natives would grow in a mix like that?
The yellow sand is my main concern, but I don't
think the plants would like pure soil conditioner, either.
Grateful for any informed advice.
NB: The types of natives I've planned are calistemons, Ricinocarpos 'Bridal Star', westringeas, a couple of chorizema cordatum, lilly pilly, Big Red and Yellow Gem kanga paws, dianella revoluta, and maybe a couple of prostrate grevilleas.