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Soil and Composting: The many benefits of rock dust

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PuddlePirate
North Ridgeville, OH
(Zone 5b)

May 25, 2010
12:14 PM

Post #7826471

Reading this article and putting its suggestions into practice has really helped me boost the vitality of my garden.

http://davesgarden.com/guides/articles/view/727/

Darius' other articles are real eye-openers, too.

Thumbnail by PuddlePirate
Click the image for an enlarged view.

sallyg

sallyg
Anne Arundel,, MD
(Zone 7b)

May 25, 2010
12:32 PM

Post #7826530

She did a great series. I just haven't followed through on things like rock dust.
PuddlePirate
North Ridgeville, OH
(Zone 5b)

May 25, 2010
12:45 PM

Post #7826577

Its effects were surprising. My strawberry patch looks like it's full of Triffids.

sallyg

sallyg
Anne Arundel,, MD
(Zone 7b)

May 25, 2010
12:51 PM

Post #7826588

I'm really thinking I may have some mineral problems. Gotta go read that again and go get the good stuff. Just planted new Tristar SB plants this spring. Where did you get your rock dust?

This message was edited May 25, 2010 2:54 PM
PuddlePirate
North Ridgeville, OH
(Zone 5b)

May 25, 2010
1:43 PM

Post #7826766

http://www.planetnatural.com/site/glacial-rock-dust.html

VORTREKER

VORTREKER
POTTSBORO, TX
(Zone 7b)

May 25, 2010
9:40 PM

Post #7828303

100% of the research over at least the last 40 years has shown that most of our soils are mineral deficient.
Puddlepirate is absolutely right. Even the very best compost you can make will be lacking in minerals. Seaweed from oceanic areas near volcanic areas like Norway are also great and should have few pollutants.

sallyg

sallyg
Anne Arundel,, MD
(Zone 7b)

May 26, 2010
1:09 PM

Post #7830155

Another writer did an article about a mineral supplement that sounded very good too. Bad on me- I just can NOT think of her name at the moment. L...ugh this is shameful. Aroid expert...LARI ANN!!


Not bad price on that 50 lb from planet natural, 18.95
PuddlePirate
North Ridgeville, OH
(Zone 5b)

May 26, 2010
2:06 PM

Post #7830404

sallyg wrote:Not bad price on that 50 lb from planet natural, 18.95


The shipping is what hurts. Best to buy plenty of other stuff, since you're gonna be paying to ship a large heavy item anyway. It's still worth it.

VORTREKER

VORTREKER
POTTSBORO, TX
(Zone 7b)

May 26, 2010
4:10 PM

Post #7830827

Puddle--I can get Green sand locally in bulk---is it as good as Rock ?Dust?
PuddlePirate
North Ridgeville, OH
(Zone 5b)

May 26, 2010
5:09 PM

Post #7831076

From what I understand, they're similar but not identical. Greensand has much more potassium (0-0-3) along with its micronutrients, and rock dust is mostly micronutrients.

Rock dust: http://www.planetnatural.com/site/glacial-rock-dust.html

Greensand: http://www.planetnatural.com/site/greensand-soil-amendment.html

VORTREKER

VORTREKER
POTTSBORO, TX
(Zone 7b)

May 26, 2010
7:22 PM

Post #7831597

Take a look at Azomite results. I put some on my tomato bed today--we'll see.
The corn on the right was planted with AZOMITE® one month after the corn on the left was planted without AZOMITE®.
Yes – one month AFTER!

Thumbnail by VORTREKER
Click the image for an enlarged view.

VORTREKER

VORTREKER
POTTSBORO, TX
(Zone 7b)

May 26, 2010
7:22 PM

Post #7831601

Sorry--forgot to thank PuddleP for his response

sallyg

sallyg
Anne Arundel,, MD
(Zone 7b)

May 26, 2010
8:16 PM

Post #7831811

Yeah I figured the shipping on 50 pounds would be substantial.
Gee, VT your pic is on the Azomite website page. Oh, is that not your corn, but your restating what they said?

sallyg

sallyg
Anne Arundel,, MD
(Zone 7b)

May 26, 2010
8:50 PM

Post #7831886

Here's the article I remembered
http://davesgarden.com/guides/articles/view/1020/
about a sea mineral product. Link in article to read more on that product

VORTREKER

VORTREKER
POTTSBORO, TX
(Zone 7b)

May 26, 2010
10:05 PM

Post #7832029

sally
Did I say, or imply, that was my corn?--I did say I put some on my tomatoes --will send pics later.

sallyg

sallyg
Anne Arundel,, MD
(Zone 7b)

May 26, 2010
10:12 PM

Post #7832045

I misunderstood! :-) Not the first time!
and won't be the last sadly. my brain is probably lacking in minerals too.

PuddlePirate
North Ridgeville, OH
(Zone 5b)

May 26, 2010
10:44 PM

Post #7832082

Anything typed after ten should get a mulligan.
nutsaboutnature
Algonquin, IL
(Zone 5a)

May 31, 2010
3:35 PM

Post #7846583

Thanks PuddlePirate for starting this thread!

This is really fascinating!!
I've heard that Green Sand is good for tomatoes, but mostly because of the potassium. I didn't know it had all kinds of minerals & I had never even heard of Rock Dust.

I glanced at both of the articles recommended by PuddlePirate & sallyg. Just amazing stuff. I'll probably end up printing them for quick reference.

We have clay & all the problems that go with it. I'd love to try it on the lawn as well as the garden beds & veggies, but we have a huge lawn so that's something that would have to happen slowly.

We have several gravel pits/rock quarries right near by so I think I'll find out if they have rock dust available at the right grain size.

Planet Natural looks like a great site, PuddlePirate. Thank you. I think that first I'd like to try to get it locally if I can & avoid the shipping.

Thanks to all that have been posting on this thread. It's an exciting new area of gardening for me to explore.!!
PuddlePirate
North Ridgeville, OH
(Zone 5b)

May 31, 2010
5:09 PM

Post #7846928

Can't wait to hear what you end up with, nutsaboutnature!
nutsaboutnature
Algonquin, IL
(Zone 5a)

June 1, 2010
6:23 AM

Post #7848068

Thanks PuddlePirate.

When you use the rock dust do you just go by "weight per sq ft" like the article talks about or do you spread it a certain thickness?
Also, do you always mix it into the soil? Have you ever just spread it on top of an existing bed?

Thanks in advance.
PuddlePirate
North Ridgeville, OH
(Zone 5b)

June 1, 2010
11:21 PM

Post #7850832

I live in a brand new development that used to be a forest. The builders removed the topsoil and left only clay and a few inches of sod. Each home has some raised beds, but they're just trucked-in topsoil with mulch on top. As a result, I've been side dressing my perennials with shovelfuls of rock dust and compost late in every summer, topped off with coffee grounds to bring the worms. Since I started in 2005 with nothing, I've just been eyeballing the mix at 50/50-ish. I figure every bit of mineralization helps when you have utter crap for soil. Every new plant goes in with a heaping tablespoon of mycorrhizae under the rootball too.

Although I have a big compost pile that gets used on perennials, flower beds and stressed areas of the lawn, my compost bin is where I mix goodies for my fruits and veggies. Whenever I start a batch, at least 20 pounds (half a bag) of rock dust goes into it along with leaves, grass clippings, shredded paper, manure, coffee grounds, dead potted plants, used potting mix, blood meal, cowboy charcoal, and kitchen scraps. I then drench the core of the bin with watered-down blackstrap molasses. Once the compost is finished, it already contains rock dust throughout, but I finish up by mixing it with the rest of the original bag of rock dust and lay it down on next year's veggie garden in mid-autumn along with a cover crop that'll die in winter.

I rotate my garden's location among three different spots to avoid problems with nutrient depletion and soil-borne diseases. Each spot spends one year lying fallow with cover crops, then one year with my Biostack sitting on it (so there's no need to move the heavy compost), and then one year being the garden.
nutsaboutnature
Algonquin, IL
(Zone 5a)

June 2, 2010
7:25 AM

Post #7851480

Wow, thanks PuddlePirate!

Sounds like you have a really organized system. I know I'll never be that organized, but you've mentioned a lot of great info & ideas for me to work with. I'm sure I can incorporate several of them. I also like your "recipe" for compost as I'm just about to start composting.

We bought our house about 8 1/2 years ago & we also have a clay base. This isn't a new subdivision (about 20 years old), but it is an area that was woodland at one time (not farmland like many developments). Fortunately they left most of the mature trees & native plants & created a bike/walking path that's at least 30 miles long (goes in both directions from our subdivision). Instead of building one development next to another, they left most of the area around in its natural state so we have lots of deer & other critters. There is also a river about 1/4 mile away. Unfortunately, we also have many of the invasive plant species that have crept in over time.

That said, they still scraped down to the clay, plus tossed in rocks, boulders & excess concrete chunks & added some topsoil over it. Every time my husband has started to dig a bed for me you wouldn't believe the boulders & such he digs up!

We've been trying to amend the beds with organic ingredients, but after learning from this thread about the lack of minerals in most soil, I'd like to try adding some back. To try to replenish the lawn (which I'd love to do) would be cost prohibitive. We just have too large of a yard. But I figured to try it with the beds a little at a time. I really your idea about adding Rock Dust to the compost pile alot. It makes perfect sense since it's recommended to mix it with compost anyway.

So far I haven't had any luck with the local quarries/gravel pits. They've all been very nice, but don't seem to use the same terminology that was used in the article so can't really tell me what their Rock Dust is screened to.

I also looked up Azomite & read more about Green Sand & they both sound very interesting as well.

Thanks so much for helping to start me on this journey!!

VORTREKER

VORTREKER
POTTSBORO, TX
(Zone 7b)

June 2, 2010
7:57 AM

Post #7851578

nutsaboutnature------I just discovered that Texas greensand, which I have access to locally, is about 20% iron. That seems a bit much to me. So be sure you know what you are adding. It took me 3 weeks to find this out on the internet and I was about to add large amounts of it. I think that would have been a mistake.
I try to constantly remind myself that even cyanide comes in an "organic" form. :(
nutsaboutnature
Algonquin, IL
(Zone 5a)

June 2, 2010
8:21 AM

Post #7851665

Thanks VORTREKER!!

That's really great to know. I would not have had a clue!
I'd also love to hear how your Tomato Plants do with the Azomite when/if you start to see some results.
PuddlePirate
North Ridgeville, OH
(Zone 5b)

June 3, 2010
4:20 AM

Post #7854222

nutsaboutnature wrote:Sounds like you have a really organized system. I know I'll never be that organized, but you've mentioned a lot of great info & ideas for me to work with. I'm sure I can incorporate several of them. I also like your "recipe" for compost as I'm just about to start composting.


It's only organized enough to make it easier for a lazy guy like me to get it done. The less lifting and carrying, the better. As for my recipe, it's mostly just what I happen to have access to. I just add rock dust, blood meal, and molasses to the pile to help feed the microherd and decrapify my garden soil with minimum primping on my part.
nutsaboutnature
Algonquin, IL
(Zone 5a)

June 4, 2010
7:32 AM

Post #7858095

You can call it laziness if you want, but the only time gardening is "lazy" is when you just sit back & enjoy the beauty you've created!

I still like your compost "recipe"... As a newbie composter I'm not to the point where any of it is "instinctive". I'm going to have to think about every ingredient I add for a while.
PuddlePirate
North Ridgeville, OH
(Zone 5b)

April 10, 2011
9:15 PM

Post #8486577

Figured I'd bump this to put the topic back on people's radar.

sallyg

sallyg
Anne Arundel,, MD
(Zone 7b)

April 11, 2011
12:24 AM

Post #8486699

It s on MY radar cuz DH now has a pickup truck, and may soon have time to run us over to the friendly local gravel pit to get some
PuddlePirate
North Ridgeville, OH
(Zone 5b)

April 11, 2011
1:10 AM

Post #8486706

I'm envious! Your garden's going to love it.

Even though I get my rock dust shipped (since I haven't found a local source), I'm going to have a blast with it this year: http://davesgarden.com/community/forums/t/1169891/

I feel like a mad scientist. Muah ha ha ha!

RickCorey_WA

RickCorey_WA
Everett, WA
(Zone 8a)

April 12, 2011
3:17 PM

Post #8490915

Thanks for the term "micro-herd". I've always felt pompous saying "soil biota" or "microfauna", and "bugs" is innacurate.

Does anyone have a suggested mail-order place to buy endo-mycorrhiza and/or other beneficial soil organisms?

I found a PDF suggesting how to "multiply" endo-mycorrhiza by growing a mixture of host plants as "bait" (grasses, legumes, onions, leeks, maize and beans, or millet or other grasses with a legume such as lentil)

The mycorrhizal fungi are supposed to infect their roots and multiply there. After at least three months of growth, cease watering and cut down the plants. (Spores are supposed to be released over the next week). Then chop up the roots to 1/2" lengths, and use them plus the soil around them as innoculum for other plants.

(I wonder if roots and nodules from nitrogen-fixing plants can be used to multiply and store those for innoculating next year's crop?


Corey
PuddlePirate
North Ridgeville, OH
(Zone 5b)

April 12, 2011
5:31 PM

Post #8491202

I just got mine on Amazon.

http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias=aps&field-keywords=mycorrhizae&x=0&y=0

RickCorey_WA

RickCorey_WA
Everett, WA
(Zone 8a)

April 12, 2011
5:44 PM

Post #8491242

Thanks!

Corey
SoFlaCommercial
West Palm Beach, FL
(Zone 10b)

April 13, 2011
7:53 PM

Post #8494101

PuddlePirate wrote:
As a result,... topped off with coffee grounds to bring the worms.

Every new plant goes in with a heaping tablespoon of mycorrhizae under the rootball too.

Although I have a big compost pile that gets used on perennials, flower beds and stressed areas of the lawn, my compost bin is where I mix goodies for my fruits and veggies. Whenever I start a batch, at least 20 pounds (half a bag) of rock dust goes into it along with leaves, grass clippings, shredded paper, manure, coffee grounds, dead potted plants, used potting mix, blood meal, cowboy charcoal, and kitchen scraps. I then drench the core of the bin with watered-down blackstrap molasses. Once the compost is finished, it already contains rock dust throughout, but I finish up by mixing it with the rest of the original bag of rock dust and lay it down on next year's veggie garden in mid-autumn along with a cover crop that'll die in winter.

I rotate my garden's location among three different spots to avoid problems with nutrient depletion and soil-borne diseases. Each spot spends one year lying fallow with cover crops, then one year with my Biostack sitting on it (so there's no need to move the heavy compost), and then one year being the garden.


Pardon the many questions and the ignorance here, PP:

I knew coffee grounds helped roses, but I didn't realize it helped worms. I have an issue with big red/brown ants living in my compost, but didn't realize that you could even PUT worms in a compost...duh! Can I put fresh coffee grounds directly into my veggie garden? What nutrients do they contribute to the soil?

What is mycorrhizae? I will most likely look it up right after posting this, but nice to know.

I thought shredded paper was bad for compost because of the ink?

You mentioned manure. How 'fresh' or 'mature'? I have a friend with horses, and she said I'm welcome to all the 'poop' I can carry off in my trailer. :) Don't know if to use it 'green' and put in compost, or to leave it somewhere in yard and let it 'mature'.

What does watered=down black strap molasses do to the compost (besides attract ants)? Does it have some nutritional content?

Anyone know of any company that sells rock dust in south florida? There's a quarry, but they're turkeys...had to deal with them before on something.

I don't understand about the crops:

One year being fallow (I guess I can look that up in the dictionary) - but I'm assuming one bed gets planted with something that doesn't get eaten, or just all of one veggie?
One year with my Biostack on it - what's a biostack?

...and in case you can't tell I was raised in the 'big city' (such that palm beach and broward counties are 'big city' (but definitely 'urban')), then you're right.

But would love to learn!

thank you.
SoFlaCommercial
West Palm Beach, FL
(Zone 10b)

April 13, 2011
8:03 PM

Post #8494122

okay, just read dirt doctor - understand the molasses.

However, by 'dry' molasses, I'm assuming they mean undiluted, right out of the bottle? How on EARTH would you spread that over an entire yard as a preventative measure? I'd think that'd get rid of the fire ants, but attract a heap of other pests... Or am I wrong?

thanks again.
hrp50
Carrollton, TX
(Zone 8a)

April 16, 2011
8:30 PM

Post #8500967

No, dried molasses is different than liquid molasses. Read the following: http://www.dirtdoctor.com/organic/garden/view_question/id/2156/
SoFlaCommercial
West Palm Beach, FL
(Zone 10b)

April 17, 2011
5:49 AM

Post #8501371

Thank you, hrp50. going to get a 5lb bag from green living.com. my zucchini are starting to bloom, so i know veggies need the extra nutrients.

postmandug

postmandug
Bardstown, KY
(Zone 6a)

April 20, 2011
8:29 AM

Post #8508639

Corey, try Arbico Organics for a LOT of different material. Sometimes during the summer they offer free shipping on some of the big bags of stuff which can really save you the money.

Doug
PuddlePirate
North Ridgeville, OH
(Zone 5b)

April 20, 2011
11:48 AM

Post #8509031

Here's the Garden Watchdog entry for Arbico Organics: http://davesgarden.com/products/gwd/c/1645/

RickCorey_WA

RickCorey_WA
Everett, WA
(Zone 8a)

April 20, 2011
12:34 PM

Post #8509148

Arbico Organics - THANKS! I had not found them.
I resopect any vendor that offers you MSDS sheets on their front page!
And they have a great collection of beneficial insects and nematodes.

Here's what I was lookiing for: they even have 1 ounce pkts for $10.

Root Maximizer Beneficial Fungi (mycorrhizal spores)
Micronized Mycorrhizal Inoculant 1 oz (approximately 3 tbsp.)
http://www.arbico-organics.com/product/Beneficial-Fungi-Root-Maximizer/organic-soil-conditioners

8 oz for $34 is getting steep for me, since I doubt that even spores will last a year or two.
But I would split that 2-3 ways with someone!

1 lb for $49 is not something I'll be doing unless I win a lottery. Those may be fair prices, but I'd rather buy a yard or two of commercial compost. (I have a very small yard, and only a few sunny spots where beds can be placed.)

(Adding to "Favorites")

postmandug

postmandug
Bardstown, KY
(Zone 6a)

April 21, 2011
7:23 AM

Post #8510818

I'm on their mailing list and even though the shipping prices for 50# bags of different amendments are quite high, they do send out special mailing sometimes where shipping is included in price or greatly reduced. However, a lot of the amendments they sell I cannot for the life of me find locally so I may have to do a mail order.

Doug
VitaVeggieMan
Clifton, VA
(Zone 7a)

April 21, 2011
8:26 AM

Post #8510944

Here's another source for mycorrhizae.

http://www.fungi.com/mycogrow/index.html

I bought their MycoGrow for Vegetables, which is available in one ounce packets for $4.95. A little goes a long way in my container garden. I haven't been using it long enough to know how well it works.
VitaVeggieMan
Clifton, VA
(Zone 7a)

April 21, 2011
8:38 AM

Post #8510960

Forgot to mention that I add a few scoops of greensand to my potting mix when planting each container. I bought a 50 lb bag at my local nursery for about $20, and it will probably last me 3-4 years.

Greensand is recommended in the fabulous book "The Bountiful Container" by Rose Marie Nichols McGee and Maggie Stuckey. If you don't already have this book, you need to order it ASAP. My copy is dirty and beat up because I always have it with my when I'm planting!

Gymgirl

Gymgirl
SE Houston (Hobby), TX
(Zone 9a)

April 21, 2011
9:11 AM

Post #8511043

Anybody know of a local supplier of Azomite in the Houston area?

RickCorey_WA

RickCorey_WA
Everett, WA
(Zone 8a)

April 21, 2011
6:06 PM

Post #8512171

Thanks, I added the myco-links to my notes. I like that they list which species are in each of their products.

Funny that most of their products are mixed ecto & endo ... but like you, I would get the all-endo stuff.

Corey

Gitagal

Gitagal
Baltimore, MD
(Zone 7a)

April 30, 2011
2:47 PM

Post #8530713

Would Builders sand" have any value as "Rock Dust"???/

How about the coarser version--with actual small stone bits mixed in,
that is used as an underlayment for pavers?

Asking--as both of these are easily available in Box Stores...

How about Granite dust...also sold in Big Box stores?

I just had a raised bed built--and will be filling it with delivered top soil.
Will be adding semi-composted, shredded leaves and some of my own
compost near the surface.

I DO NOT want to spend $$$$ for having to buy anything on line...
My soil will be--what it will be...

Looking for very cheap alternatives...

Thanks, Gita
PuddlePirate
North Ridgeville, OH
(Zone 5b)

April 30, 2011
6:36 PM

Post #8531161

Builders' sand: nope. Coarser sand: nope. The individual pieces are too big for microorganisms to use easily, and they're not made of a wide variety of minerals. Not much good, even if you were to pulverize it to powder.

Granite dust: probably decent. As the original article puts it:

Quoting:Locally, I have granite dust available from the gravel pits, which is okay to use but not best. The mixed gravel dust from the local stream beds is better. A better yet rock dust comes from glacial gravel or volcanic rock like basalt. Another is montmorillonite. Montmorillonite is a very soft phyllosilicate mineral that typically forms in microscopic crystals, forming a clay. It is the main constituent of the volcanic ash weathering product, bentonite.


It'll probably help.

Gitagal

Gitagal
Baltimore, MD
(Zone 7a)

April 30, 2011
7:39 PM

Post #8531307

Puddle...

I have NO idea where here I could get any of it...never even heard of ir until all this talk here...
I will just go with the good ole Top Soil amended with my leaf compost.

I don't think any farmers of gardeners here use any of that "dust/gravel stuf"--and things still grow...

Thank you all for your suggestions and explanations.
It has been educational...and will stay in my mind...I appreciate it...

Gita
PuddlePirate
North Ridgeville, OH
(Zone 5b)

April 30, 2011
8:46 PM

Post #8531418

The granite dust should help somewhat. Sure, it's not perfect. But whose garden is?

RickCorey_WA

RickCorey_WA
Everett, WA
(Zone 8a)

April 30, 2011
10:57 PM

Post #8531541

I don't think real "sand" contributes useful mineral nutrients, because I think sand is just fine quartz (silicon dioxide). No matter how fine it is, there just aren't any good mineral ions in it to be leached out.

On the other hand, COARSE sand does help drainage and aeration somewhat, especially if it is big enough to be called "grit" (say, 1-4 or 5 mm).

Crushed ROCK ought to offer some minerals, depending on the source rock, and I gree that volcanic rock ought to be richest.

For minerals, the finer it is crushed, the better (down to dust).

For drainage and aeration, the bigger the better (up to around 5 mm or almost 1/4", I would say.

And big crushed rock is much better than coarse sand for this becuase grains of sand are mostly close to cubical or spherical. They tend to pack down compactly with very small open spaces. Crushed rock grains have irregular shapes and sharp points, and tend to be surrounded by larger void spaces than sand grains.

My belief is that sand - even as small as medium - helps heavy clay soils to be more friable (tend to break apart instead of becoming one big continuous airless pudding) - if they have at least SOME organics in them, like compost, leaves, clippings, sawdust or manure.

Clay with sand and little compost is still very prone to compaction and being hard when dry. Heavy clay just NEEDS composted organics and avoidance of compaction when wet, or nothing much will help it.

That's the belief I've come to over a few years of struggling with very heavy clay, and a cheap nature, and almost no free sources of compost.

If the soil doesn't have pretty decent structure, micro nutirients and even macro nutirents won't do much good. Roots can't pentrate airless soil, flooded soil, or very-heavily-compacted soil.

Once the soil structure is at least half-decent, micronutrients from rock dust are great, and one of the few things you can add to soil that will be a permanent improvement. And rock dust is probably better than highly concentrated soluble micronutrients - I doubt if you can overdose a soil with rock dust!

Crushed rock excites me more as a way to improve drainage and aeration, than as a source of nutrients. My soil NEEDS much-improved drainage and aeration BADLY! I am guessuing that my high clay content probably already has a fair amount of this and that mineral. And all that clay is tenacious about holding onto any ions that I bring in as I add compost and mulch.

Corey
huggergirl
Columbia City, IN
(Zone 5b)

May 1, 2011
4:05 AM

Post #8531651

I use a recipe for fertilizer,made with bonemeal ,bloodmeal, and greensand.well just started using 2 years ago...You have mentioned some very interesting things.I definitly ,will be adding greensand to my flower pots ,cant wait to see if there is a difference.i didnt know how beneficial rock dust is ,and Important .Makes great sence now.Thanks
mraider3
Helena, MT

May 1, 2011
5:50 AM

Post #8531765

I have four locally available source of free crushed rock. I picked up six five gallon buckets from the first source the other day and it is much like sand. The other sources said there's was larger than the industry standard of 'minus 200', which according them it contains chips as well. I am experimenting with some rogue tomato plants today making a potting mix which includes these crushed rock fines, wood chip fines, well aged cow manure, some spent worm media and pearlite. Will see how this goes.
patti47
Lynnwood, WA
(Zone 7a)

May 17, 2011
7:29 AM

Post #8568990

I have been thinking of getting some rock dust from a monument place that's nearby. That's where they carve headstones for grave markers. It might be free or at least cheap. Any thoughts on whether that's a good choice?
PuddlePirate
North Ridgeville, OH
(Zone 5b)

May 17, 2011
8:23 AM

Post #8569088

The kind of dust matters a lot. I don't know if marble dust is worth using or not. According to what I've read, glacial rock dust has a good variety of minerals. Granite dust is so-so.

If the monument place can give you several kinds of dust from different types of stone, go for it.
patti47
Lynnwood, WA
(Zone 7a)

May 18, 2011
6:22 AM

Post #8571146

Thanks Puddle. Another thing I have wondered about is lava rock. It is used around here sometimes as a mulch. If I could crush it somehow, would that be good for minerals? Without the crushing, do you think it makes a mineral contribution in the garden?
PuddlePirate
North Ridgeville, OH
(Zone 5b)

May 18, 2011
10:04 AM

Post #8571616

All rocks will weather, even boulders. Lava rocks will add some minerals, I guess. The smaller the pieces, the faster it'll weather. From what I remember, though, lava sand is used more often for its porous structure or for its attractive color, & not for its minerals.

RickCorey_WA

RickCorey_WA
Everett, WA
(Zone 8a)

May 18, 2011
11:55 AM

Post #8571823

My guess is that anything porus will be crumbled faster by frosts than solid rocks.

(I would say that "new" volvanic minerals have more garden potential than "old" eroded fines, but anything crushed is "new".)

I've also read the suggestion that if you buy crushed rock, you'll get "more minerals" from volcanic rock or "mixed" sources like crushed river gravel than from one rock type like granite.

But I don't really know. Wouldn't a sedimentary rock already contain a lot of variety?

I personally worry more about soil structure, drainage and aeration than micronutrients, on the theory that I would worry more about drowning than vitamin deficiency.

But if you have pretty good soil, rock dust for minerals is a great potential improvement, and long-term.

I like the idea of adding coarse pumice or tuff for structure & drainage, then counting on it breaking down over decades for minerals.

Corey
tommyr2006
Poughkeepsie, NY

June 10, 2011
6:33 PM

Post #8623027

Mycorrhizae seems to be the latest gardening fad. It's not cheap and you don't need it IMHO. Just make sure your soil PH in in the right range for what you're growing. Since I can't find rock dust here I use greensand for trace minerals. Keep adding compost and organic matter to your soil and you'll be just fine!

sallyg

sallyg
Anne Arundel,, MD
(Zone 7b)

June 11, 2011
6:36 PM

Post #8624764

RickCorey_WA wrote:

I personally worry more about soil structure, drainage and aeration than micronutrients, on the theory that I would worry more about drowning than vitamin deficiency.

Corey


That does make sense when you say it that way

sallyg

sallyg
Anne Arundel,, MD
(Zone 7b)

June 11, 2011
6:39 PM

Post #8624770

tommyr2006 wrote: Keep adding compost and organic matter to your soil and you'll be just fine!


And anything that was able to grow, and then rots, will return all of the mineral content that it sucked up to grow with.

huggergirl
Columbia City, IN
(Zone 5b)

June 12, 2011
6:05 AM

Post #8625294

I need to work on my compost pile,thanks for the Nudge..LOL..Great Info...it is soo hard to really understand ..I keep trying ...LOL

RickCorey_WA

RickCorey_WA
Everett, WA
(Zone 8a)

June 13, 2011
5:46 PM

Post #8628414

I agree that, if you have lots of compost, you probably have at least SOME of everything you need.

>> I would worry more about drowning than vitamin deficiency.

If I ever get all my rasied beds amended to the point of having good drainage and aeration, and plenty of organic matter ... then I WILL worry about micronutrients. But I'll have to find a cheap source of soil analysis.

My suspicion is that, with all the clay I have, micronutrients will be the least of my problems. But you never know, until the soil test comes back with something like: "you have a HUGE boron deficiency", and a tiny pinch of something makes everything grow twice as green.

Or, worse, "you have an excess of XYZ, so Iron and ABC will be insoluble and unavailable, good luck!"

Corey
huggergirl
Columbia City, IN
(Zone 5b)

June 14, 2011
5:39 AM

Post #8629278

You said it corey,makes my head spin...i have so many different beds,i would have to have the soil tested in every bed ,that would not be very cost effective ..LOL

RickCorey_WA

RickCorey_WA
Everett, WA
(Zone 8a)

June 14, 2011
3:03 PM

Post #8630425

>> i have so many different beds,i would have to have the soil tested in every bed ,that would not be very cost effective

I've begun thinking that I should take every opportunity I have to mix up the soil in my different beds. Well, at least spread some soil from my better beds into the worse ones, and remove soil from the worst ones and cycle that through my "dirt pile" where i screen and mix with amendments and compost.

Part of that would be to spread good soil microbes into the poor soil. Part would be to average out the weaknesses, so that one sample taken from the three biggest beds, plus one taken from my dirt pile, would be informative about the whole yard.

Mainly, I'm in doubt about pH. There's no doubt in my mind that everything is low in N, P, K, organic matter and iron. Probably low in sulphate and Mg. Too much clay, not enough sand and grit.

Corey
huggergirl
Columbia City, IN
(Zone 5b)

June 15, 2011
4:58 AM

Post #8631472

Im not going to do all that ...LOL... I do try to amend as well as I can ,its kind of the survival of the fittest.. I will stick to using my organic fertilizer and hope for the best. I have yellow clay or Had,talk about live an learn...I dug a lot of it out and replaced it,way too hard to try to amend it enough,I do cut a little in every now an then.Ive had to add sand in a few areas. Ive been using Ironite a little too,our soil is a little acidic here,not bad.But Im sure my soil is all confused .Like Me...LOL

RickCorey_WA

RickCorey_WA
Everett, WA
(Zone 8a)

June 15, 2011
11:29 AM

Post #8632187

One good thing about having "patchwork soil" - if it's different in every bed, each kind of plant can tell you what it likes best, if you scatter some seed or divisions around.

Corey

sallyg

sallyg
Anne Arundel,, MD
(Zone 7b)

June 16, 2011
11:00 PM

Post #8635527

Corey if you need sulphate and magnesium, you might like some epsom salts (Mg sulfate)

RickCorey_WA

RickCorey_WA
Everett, WA
(Zone 8a)

June 17, 2011
7:29 PM

Post #8637469

I agree that epsom salts can be handy for sulphate, though dolomite lime is my preferred source of Mg. I've always lived where there was acid soil. Maybe under the Rhodies and Azaleas!

I worked at a place once, where they used several 50 pound bags of industrial grade ferrous sulphate every week. I scooped up a jar to supplement chelated iron fertilizers (that was for indoor growing).

When petioles got purple, I would water or spray with both iron and Mg. Why try to figure out which was the problem, when curing both was easy?

Corey


sallyg

sallyg
Anne Arundel,, MD
(Zone 7b)

June 18, 2011
6:43 AM

Post #8638090

Petioles of what- Azaleas and Rhodies, or others?

You now chemistry better than I do- my soils is already acid so I don't expect I need sulphates for my azaleas. And then I don't feel they would want lime either. Whats a gal to do?

Gitagal

Gitagal
Baltimore, MD
(Zone 7a)

June 18, 2011
6:59 AM

Post #8638115

Yikes----

I sort of had forgotten about Epsom salts---so, after you mentioned it,
Sally, I went out and sprinkles some around everything...
My Brugs-(I know they like it), my tomatoes and beans and squash
and everything else, Just a couple TBS each.

Hope I did not screw up??????? I tend to do all--or none...

Gita
rouge21
Canada
Canada
(Zone 5b)

August 24, 2011
3:29 AM

Post #8774146

For those Canadian gardeners in Ontario I just picked up a couple of bags of 'rock dust' from GLOBALREPAIR.ca.

They call their 'soil conditioner' product "Rich Valley"http://www.globalrepair.ca/fertilizer.htm.

And I quote from their website:

"Contains rare volcanic, metamorphic and sedimentary minerals, calcium, rock phosphate and humates,..."

darius

darius
So.App.Mtns.
United States
(Zone 5b)

August 24, 2011
5:08 AM

Post #8774194

rouge... that sounds like a lovely mix!
margocstn
Savannah, GA

December 5, 2011
4:20 PM

Post #8917721

I ordered my rocksand just now from planet natural, it was cheaper total than amazon. I got some espoma green sand today from a store.

I only have 7 raised beds and a compost heap, I figure 100 lbs should get me started. I spread the little bag of green sand in the beds just to get a start. I planted my winter greens today.
Indy
Alexandria, IN
(Zone 6a)

December 6, 2011
1:20 PM

Post #8918910

I put a moderate amount of Azomite on the gardens last year. It comes with an analysis. It can be picked up at dealers in some areas or ordered from Fedco Seeds/

http://www.azomite.com/

This message was edited Dec 6, 2011 4:39 PM
margocstn
Savannah, GA

January 1, 2012
3:42 PM

Post #8950408

I got my rockdust and added it to my soil and compost heap. I didn't add it all at once since I already had seeds in the ground. I top dressed and side dressed, then I watered it in. I applied it more than once.

I don't have much of a winter garden, just a few greens, so I probably won't be able to see the effect till later this summer. I have noticed that my soil does not dry out nearly as bad as the last couple winters. I struggled to keep my swiss chard bed damp enough but it's easy now! It's like the soil is more wettable, plus it doesn't go through as fast. I thought it was my imagination at first.

I ordered some azomite last week. I figure it's best to have additives from a few differant sources. I'm planning on ordering more rock dust this spring as well.

darius

darius
So.App.Mtns.
United States
(Zone 5b)

January 1, 2012
4:10 PM

Post #8950443

Margo, one of the amazing things about greensand (and I still don't understand how it works) is that it loosens heavy clay soil yet will help sandy soil retain water better.
margocstn
Savannah, GA

January 1, 2012
4:44 PM

Post #8950484

I got a couple little bags and put that in already, like I said, I'm diversifying my soil ammendments. I'm going on the notion that it is unlikely I would use too much. I have 5 10ft raised beds and 2 4x8 raised beds. Plus my compost heap. I have enough soil in my beds that I can remove some to put in fresh compost, I'm going to start putting extra in my front yard.

I got 100lbs of rock dust and have only used half on one bag so far. That gives you an idea of how much I've used. I would have thought it would have taken much more to have that effect.

I wonder if it's possible to use too much? I'm planning on adding it all when I redo for my summer beds. That's why I want to get extra to add. It's my understanding that it degrades very slowly, so adding a large bulk at once will last a long time.
rouge21
Canada
Canada
(Zone 5b)

January 1, 2012
5:08 PM

Post #8950508

margocstn wrote:I wonder if it's possible to use too much?


I wonder similarly. Right now I hand sprinkle it on my lawn, add a handful or two when planting or transplanting perennials and this past fall I hand spread it throughout my perennial gardens.

When I begin composting in earnest I will for sure add it to the pile.

But is there such a thing as "too much" rock dust?

darius

darius
So.App.Mtns.
United States
(Zone 5b)

January 1, 2012
5:12 PM

Post #8950518

Not that I've ever read.
huggergirl
Columbia City, IN
(Zone 5b)

January 2, 2012
3:59 AM

Post #8951001

Whats the difference between rock dust and greensand ?? Tamara

darius

darius
So.App.Mtns.
United States
(Zone 5b)

January 2, 2012
4:11 AM

Post #8951007

There are many types of rock dust. Each area around the country, or the world, has different kinds of rock and sediment layers. The greensand from New Jersey is largely from ancient marine layers.
MaryMcP
Phoenix, AZ
(Zone 9b)

January 27, 2012
5:09 AM

Post #8983814

Last year, late summer/early fall, I ordered the 50# bag of glacial rock dust from Plantet Natural

http://www.planetnatural.com/site/glacial-rock-dust.html

and worked this into my beds. All 50# have been used up as well as 12# of crab shell from Neptunes Harvest -

http://www.neptunesharvest.com/cs-612.html

How long does this stuff last? I'm prepping my beds now for spring tomato planting, is there still sufficient nutrients left from last fall or do I need another 50#'s of rock dust and 12# of crab shells?

At that time the beds were also amended with 1-yard of 'sandy loam compost' from the local landscaping supply company and some of my own compost. I may get another load of the sandy loam mix but I sure wish I had a dump truck. I've a bum shoulder and getting that stuff out of the back of my truck is several hours of serious shoveling.

Anywho - will it be over-kill to add more now? How often do you folks add these types of amendments? The rock dust especailly.

Thanks for any feedback.

darius

darius
So.App.Mtns.
United States
(Zone 5b)

January 27, 2012
6:51 AM

Post #8983936

How many square feet did you cover with your 50#? I don't think too much does any harm.
Here's the suggested application rates for your glacial dust:
DIRECTIONS FOR USE:
Spread 50-150 lbs. Glacial Rock Dust per 1,000 square feet and work into the soil prior to planting. During the growing season, boost plant health by side-dressing in crop rows or around the drip line of trees and shrubs. It's best to work side-dressings into the top 1-inch of the soil.

Here's what my (2 different) old notes for greensand say:

Application Rates
Application rates vary depending on soil conditions and intended use. As a soil conditioner, applications of 25#/1000 ft2 (or 1000#/acre) are recommended. To correct potash deficient soils, anywhere from 20# to 100#/1000 ft2 (or 800# to 4000#/acre) would be applied, depending on the extent of the deficiency.


Light Application 5 to 10 lbs. (or up to 1 cup for every 5 sq. ft.) per 100 square feet.
Medium Application 15 to 30 lbs. (or up to 1 cup for every 2 sq. ft.) per 100 square feet.
Heavy Application 40 to 80 lbs. (or up to 1 1/4 cups for every 1 sq. ft.) per 100 square feet.
Per plant use 1/3 cup.

darius

darius
So.App.Mtns.
United States
(Zone 5b)

January 27, 2012
7:14 AM

Post #8983959

Mary, you can download the Product Face Sheet on your brand of rock dust here
http://www.gaiagreen.com/products/product_detail.asp?ID=4
MaryMcP
Phoenix, AZ
(Zone 9b)

January 27, 2012
9:49 AM

Post #8984189

Thanks Darius...that spec sheet said "...up to once per year or as desired." so I guess I can [or cannot] add more now. Shipping is the killer as that is $10 more than the product itself. If I can find some locally I'll get it but wait if I need to order from an on-line supplier.

Hard to say what square footage I covered, I have multiple gardens scattered all around. I used one raised bed as my 'mixing bowl', dumping in wheelbarrow loads of the sandy loam mix, adding a bunch of the rock dust and crab shells, mix it up and then wheelbarrow it out to other beds. DH, watching this practice, commented..."Hey, didn't you just dump that dirt INTO that bed? And now you are taking it out???"

Gitagal

Gitagal
Baltimore, MD
(Zone 7a)

January 27, 2012
10:37 AM

Post #8984243

Mary,

I will have you know that, because of the link you posted, to "Planet Natural"--I just spent $50+.

Mostly--I was happy to find a source for the 3"x5" yellow sticky pads for use in the house to trap gnats.
Got 25 of them for $8.95 and 10 wire card holders for $3.50.
I also ordered some coir bricks (4) and some liquid See weed/Kelp fertilizer for houseplants. Came in a qt. size.
Concentrate---1/2 tsp to the gallon for "light" fertilizing. One tsp for a more heavy feeding.

I must say--their shipping charges are pretty high! Oh well...I am NOT used to ordering things on-line...
Gita
Indy
Alexandria, IN
(Zone 6a)

January 27, 2012
10:59 AM

Post #8984265

I have one garden that has been gardened for nearly 80 years and was farmed before that. Another has continuously been gardened for 39 years and the third for about 10 years.

I think it is reasonable to assume that some of the micro minerals could be a bit used up or leached unless one has done a super job all those years...and that starting from super deep rich soils. Leaching removes minerals in most areas. Arid areas may not need additional rock powders.

Anyway I added a small/moderate amount of Azomite a year ago. Crops are great...course they were great before too!
MaryMcP
Phoenix, AZ
(Zone 9b)

January 27, 2012
11:18 AM

Post #8984279

gitagal...I know the feeling...that's how I get LOTS of stuff. Folks here post and I just can't resist.

RickCorey_WA

RickCorey_WA
Everett, WA
(Zone 8a)

January 27, 2012
3:08 PM

Post #8984562

>> I used one raised bed as my 'mixing bowl', dumping in wheelbarrow loads of the sandy loam mix, adding a bunch of the rock dust and crab shells, mix it up and then wheelbarrow it out to other beds.

I think that's a good idea, if the mixing-bowl-bed has rich organic soil with lots of things growing in it (meaning lots of soil life, not plants!) I do the same thing so that the living population mixture from my helthiest is continually being re-innoculated into my younger, less improved soils.

On the other hand, you could save some wheelbarrowing by giving every bed direct shots of compost or manuare or mulch whenever avialable.

The next is just my opinion, take it with a grain of salt if no one else confirms it. The length of time rock dust remains effective depoends on how fine the 'dust' is. If it were EXTREMELY fine flour, it might be decomposed completley in only a few years. But if it were very slightly coarser, say "dust" instead of "flour", I personally would expect it to last for years or many years.

remember, you are wiating for a grain of ROCK to dissolve completely. I suppose it happens faster in acid soil or with acid rain, and in a very active, organic soil, and in well-aerated warm soil.

But I always thought that rock dust additions were scheduled 5-10 years apart. I could be wrong. Probably the cheaper forms of rock "dust" are not ground as finely as more expensive kinds.





MaryMcP
Phoenix, AZ
(Zone 9b)

January 28, 2012
4:44 AM

Post #8985072

That's an interesting analogy Rick...waiting for a grain of rock to dissolve. The Glacial Rock Dust from Planet Natural was flour-fine. There's a feed store a hundred miles north that sells Azomite and I may get some of that and see if it's different. Thanks for the input.
Indy
Alexandria, IN
(Zone 6a)

January 28, 2012
10:40 AM

Post #8985445

MaryMcP, I am posting a link to Azomite. You can check the analysis sheet on the site. It likely compares with some other dust.

http://www.azomite.com/
MaryMcP
Phoenix, AZ
(Zone 9b)

January 28, 2012
1:57 PM

Post #8985669

Thanks Indy. I saw that site and have researched and found a dealer in Arizona. Although they are not in Phoenix, someone there will be traveling to Phx next Saturday and is willing to transport a 40# bag for me. We'll meet in a shopping center parking lot off the freeway, just like a clandestine 'deal'. Hahahah. Once I turn this in, I should be good for a good long while.
tropicalnut777
Provo, UT
(Zone 5a)

January 28, 2012
6:06 PM

Post #8986007

i didnt see discussion on "lava sand" or did i miss it???
has anyone tried it?? the promoters/sellers say it has a high cation exchange capacity..
guess its suppose to help hold fertilizer in soil..not get washed away..and has is suppose to be
"paramagnetic" ?? now i like to think im a pretty opened minded guy..but reading on this.. sounds
a bit unscientific..??
anyone?? thoughts?
i like greensand.. my roses and tomatoes love it.. of course in correct amounts.. to much of anything
isnt good.. except ice cream,coffee,and pizza.. LOL
evelyn_inthegarden
Sierra Foothills, CA
(Zone 8a)

January 28, 2012
8:26 PM

Post #8986138

You can get Azomite from the seller:

http://www.wheatgrasskits.com if you wish to purchase it online. I have bought from her 2 years in a row. She was on ebay, and I think she is on Amazon as well.

This message was edited Jan 30, 2012 7:15 PM
evelyn_inthegarden
Sierra Foothills, CA
(Zone 8a)

January 28, 2012
8:26 PM

Post #8986139


I'm not sure why it posted twice...sorry!

This message was edited Jan 28, 2012 8:39 PM
Indy
Alexandria, IN
(Zone 6a)

January 30, 2012
1:51 PM

Post #8988376

Some soil minerals get leached into the subsoil or away in drainage in areas of good rainfall and these areas tend to be low in some minerals. In desert areas the minerals don't disappear very fast oftentimes. Still minerals will not be there if they were never there in then first place unless they have been added somehow.
tropicalnut777
Provo, UT
(Zone 5a)

February 23, 2012
7:44 PM

Post #9017755

with lava sand.. ive checked prices around..and im thinking..i should just get some lava
rock at big box store..crush it and use as lava sand..???
anyone else try this???
im so anxious to get gardening..and its turned chilly here.. again.. sigh.. LOL
lettuce is going good though.. probably in a month start another batch..
much thanks...
paani
Saint Louis, MO
(Zone 6a)

February 27, 2012
1:23 PM

Post #9022210

1/4 inch of 110 year old brick mortar dust just got deposited on our gardens beds, compliments of tuckpointers working next door. Is it "rock dust" I should be happy about ?? !

It predates Portland cement. According to discussions on the oldhouse journal site, it's likely to be "slaked lime and sand".

In another thread in this forum, Ozark said, "I did some reading, and found that it's not good to add fertilizer and lime to a garden at the same time - there's a reaction between them that's not good for soil chemistry."

everything is shooting up in this non-winter, and I was going to fertilize at least the spring bulbs soon. Now I'm wondering whether that's a bad idea with the thick mortar dust.

I guess the question is whether limestone that old is chemically active or not?

This message was edited Feb 27, 2012 3:29 PM

This message was edited Feb 27, 2012 3:48 PM

Gitagal

Gitagal
Baltimore, MD
(Zone 7a)

February 27, 2012
3:07 PM

Post #9022353

I believe fertilizing your bulb beds with some organic, slow-release fertilizer is what is usually
done. I did all my bulb plantings a couple of weeks ago.

Same goes for the Holly Tone for all your acid-loving plants. Twice a year. Late fall and early spring.

I like to use all the Espoma "Tones"...They are good for the garden--are not chemical and are slow-release.
Plant Tone
Bulb Tone
Holly Tone
Rose Tone

Of course--everything is early this year. But--you can still do it.

For your first feeding of your roses--add a good handfull of Epsom Salts (Magnesium Sulphate)
around the Roses as well. This promotes new canes to grow up from the base.

Gita
paani
Saint Louis, MO
(Zone 6a)

February 27, 2012
3:22 PM

Post #9022372

gitagal,
thanks for the good advice. That's about what I normally do as well.
I almost started fertilizing awhile back too, but decided to wait till now -- and then boom, this happened.

I'm hoping somebody can tell me what the impact this thick layer of old brick mortar is going to be

-- and whether I should alter my usual fertilizing as a result?

Looks like the garden moved to mars at the moment!!
Indy
Alexandria, IN
(Zone 6a)

February 27, 2012
3:30 PM

Post #9022386

If it were me, I would go ahead and do any fertilizing. The mortar likely will take 3 oe 4 tears to break down.
paani
Saint Louis, MO
(Zone 6a)

March 15, 2012
7:36 PM

Post #9044382

thanks Indy. Missed your reply till now, but have been pretty much doing as you advised -- a bit behind the season, which jumped straight to summer!

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