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Aloha All,
Does anyone know if the Pepeekeo Top Soil from Puna rock is good?
Does it have weed seeds in it?
Chemicals & Pesticides?
I've heard that the Soil from Sugar Cane areas is contaminated with these things.
Mahalo for replies. KW
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I have used it a ton, but I amend it at least 30-40% compost and then 10-15% black cinder + other things like rock dust etc.
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03-06-2023, 04:33 AM
(This post was last modified: 03-06-2023, 04:51 AM by terracore.)
It's not topsoil, it's subsoil. It's like clay and it doesn't drain on its own. I recommend getting the "cinder soil" variant which is 50% black cinder mixed in with it so it can drain. They don't make the blend I'm about to describe, but you can DIY it: Get a half load of cinder soil, pay for it, and then get a half load of the mac nut compost, pay again, and try to mix it up when you unload it. It's a lot closer to "top soil".
I did use one of those soil tests that measures the NPK and the Pepeekeo stuff was deficient in all of them. The compost will help with that, but it will need further amendments to be good soil. Rock dust (Azomite) is a good idea and you might need to correct the pH depending on what you're growing. I did measure the pH but I forgot which way it was leaning.
If getting it from Puna Rock, only buy these things after a long dry spell. Since they charge by weight you don't want to buy it after heavy rains and pay for all that water.
Edited to add: No weed seeds, etc. I think it's mined from too far down to have stuff like that. I have received chunks of wood, rocks, etc but its mostly just soil. I didn't do any chemical etc screenings on it but I think the soil they are digging out now is from deep enough it predates the sugar daze and most of that stuff stayed in the topsoil or ranoff. The sugar people used a lot of arsenic which naturally occurs in deep soil anyway, so even a positive test would need to be reconciled with naturally occurring background levels.
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Good questions about the Pepeekeo soil. It could have weed seeds in it from sitting at their quarry for awhile. Otherwise I agree with Terracore's assessment.
I buy a 1/2 ton of black cinder, then go to ACE and buy about a dozen bags of steer manure that can be thrown in the bed on top of the cinder.
Back home I mix them in a wheelbarrow. Some county mulch added in would be a nice mix.
