Rock Dust?

[pdxwindjammer]

I did a search on this forum but didn't find much info about it. Has anyone had great success with adding rock dust to your soil? I am considering it but would love to hear your stories on how it affected your garden.

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

http://www.nytimes.com/2004/06/24/ga...does-grow.html

[RobinB]

Very interesting articles! There are a lot of quarries around here. I think this deserves some investigation over the Winter!

[Doug9345]

I have several thoughts on this.

If an area is missing a trace mineral you aren't apt to get it near by.

Rock dust is heavy. It's got to be in the area of 2500 lbs per yard. Very expensive to move any distance.

I think if you pick the right rock dust based on a good soil test it could help.

If you are just trying to over come depletion I think I'd lean toward gathering organic material and planting deep rooted crops for compost.

The exception being ag lime.

[COMPOSTER]

I am currently using Basalt dust from a local quarry. I started last year with a dust that was reported to me to be 90% thru a #200 mesh screen. I added 1/3 lb /sq ft with my regular amendments of home made compost, dolomite lime and an organic seed meal fertilizer. This year I added another 1/3 lb / sq ft of a reported 50% thru a #200 mesh screen. So I'm up to 2/3 lb/sq ft. I'm proceeding with caution because I am in the continuing process of researching the use of using rock dust. My main interest is increasing the nutrient density and improving the taste of the food I grow. I do not use any chemicals in my gardening. My experience so far is that I believe that I am growing the best tasting vegetables I have ever grown. I routinely have other folks who I give produce to say that it is the best tasting produce they have ever had. Although I have no scientific proof that my yields are higher than before the rock dust, they continue to be excellent. My earthworm population continues to increase. I have run a controlled experiment with a small sample of 2 sets of tomatoes and believe the rock dust amended tomatoes were superior. However the sample size was too small to be conclusive. I'm very encouraged by the results so far. And by the way, I have picked up about 1800lbs from the quarry so far for free.

I started a thread on this forum called soil building for nutrient density which I will be updating shortly.

Glenn

[simmran1]

Pdx,

One thing I can contribute is a photo I took when our organic gardening club visited a natural farming operation last July. Everyone in attendance was impressed by the garden edibles area, including myself.

Here’s a link to where we were at: http://www.growingngracenaturalfarm....egetables.html

Anyway, I asked what their ‘secret’ to abundant success was, and he told us about their annual re-mineralizing. So I took a picture of the brochure:

http://s494.photobucket.com/user/sim...ng%20N%20Grace

So you can google Planters Foundation Minerals, - this is a source that some may find useful. -Randy

[pdxwindjammer]

Composter, I wish I had such a resource!

I think using rock dust to remineralize is a great idea. I did buy a 50 lb bag of Gaia Green glacial rock dust and have been sprinkling it around all my winter veggies. I am going to liberally sprinkle it on my community garden plots and then mulch with leaves to keep the weeds down. Then plant in it next spring and see what happens! I have heard it makes the veggies more delicious and nutritious as well.

[COMPOSTER]

Originally Posted by pdxwindjammer

Composter, I wish I had such a resource!

I think using rock dust to remineralize is a great idea. I did buy a 50 lb bag of Gaia Green glacial rock dust and have been sprinkling it around all my winter veggies. I am going to liberally sprinkle it on my community garden plots and then mulch with leaves to keep the weeds down. Then plant in it next spring and see what happens! I have heard it makes the veggies more delicious and nutritious as well.

pdxwindjammer, If rock dust is as valuable a resource as my research says it is I am very lucky. Not only does the quarry give it to me for free, they are very nice about it. The gentlman that I have dealt with 2 years in a row took me on a tour of the operation, showed me how it was screened, gave me a choice of mesh size and provided me with an official analysis of the rocks that were being used. All this just for the asking. It's a waste product. They have thousands of tons of it. My only regret is that I do not have a truck or I would get 3 times as much.

As I have stated in my thread on building soils for nutrient density, the great thing about the rock dust is once you have remineralized you should not need to do it again for years if not decades.

Glenn

[kath]

Originally Posted by COMPOSTER

. Not only does the quarry give it to me for free, they are very nice about it. The gentlman that I have dealt with 2 years in a row took me on a tour of the operation, showed me how it was screened, gave me a choice of mesh size and provided me with an official analysis of the rocks that were being used. All this just for the asking.

Glenn

We have several quarries very close by but when I inquired a couple of years ago by telephone after first hearing about the advantages of using rock dust no one knew what I was talking about. Maybe I need to show up in person? Do you have any tips about what to say, etc.?

kath

[COMPOSTER]

Originally Posted by kath

We have several quarries very close by but when I inquired a couple of years ago by telephone after first hearing about the advantages of using rock dust no one knew what I was talking about. Maybe I need to show up in person? Do you have any tips about what to say, etc.?

kath

kath, The first time I just showed up and started the conversation by saying that I was an organic gardener and wanted to see if I could purchase some rock dust and fill up some containers. Because quarries are hazardous areas they had me sign a release to be on the grounds and then brought me to an area to park my car. They met me there with a bucket loader filled with about 5 yds of what they referred to as "float." The material was 90% through a #200 mesh screen and was very similar to the consistency of talcum powder. Unfortunately I was only able to put about 600 lbs in my car. The second time I had an SUV and was able to pick up around 1200lbs. Both times I have gone I made sure I went around 1:30 in the afternoon to avoid any busy times or lunch break.

Glenn

[kath]

Originally Posted by COMPOSTER

kath, The first time I just showed up and started the conversation by saying that I was an organic gardener and wanted to see if I could purchase some rock dust and fill up some containers. Because quarries are hazardous areas they had me sign a release to be on the grounds and then brought me to an area to park my car. They met me there with a bucket loader filled with about 5 yds of what they referred to as "float." The material was 90% through a #200 mesh screen and was very similar to the consistency of talcum powder. Unfortunately I was only able to put about 600 lbs in my car. The second time I had an SUV and was able to pick up around 1200lbs. Both times I have gone I made sure I went around 1:30 in the afternoon to avoid any busy times or lunch break.

Glenn

Thanks for the tips, Glenn- gonna have to give this another try. How do you know that it "was 90% through a #200 mesh screen"?

kath

[nnjjohn]

Glenn, is rock dust from slate yards? I pass plenty slate yards where I camp in the summer. Are similar amendments available in garden centers? tia

[RayR]

Originally Posted by nnjjohn

Glenn, is rock dust from slate yards? I pass plenty slate yards where I camp in the summer. Are similar amendments available in garden centers? tia

nnjjohn, slate is a hard metamorphic rock originating from shale which is composed of very fine clay particles, so it weathers very slowly into very fine clay particles. Probably not a good idea if you already have sticky clay soils. Not much valuable mineral content there either other than calcium, magnesium and iron mostly I think.

[nnjjohn]

Originally Posted by RayR

nnjjohn, slate is a hard metamorphic rock originating from shale which is composed of very fine clay particles, so it weathers very slowly into very fine clay particles. Probably not a good idea if you already have sticky clay soils. Not much valuable mineral content there either other than calcium, magnesium and iron mostly I think.

I believe you Ray, actually , my jersey soil contains enough sand stone and as you say sticky clay soil .. I just can't wait for those ph probes i ordered online for 4 bucks each.. going to be sure my soil ph is adequate for next season before adding any soil amendments, ty too Ray

[kath]

Originally Posted by kath

Thanks for the tips, Glenn- gonna have to give this another try. How do you know that it "was 90% through a #200 mesh screen"?

kath

Sorry, Glenn- just reread the thread and found that the answer was in a previous post. We're going to hit a couple of quarries today and see what happens.

kath

[COMPOSTER]

Originally Posted by kath

Sorry, Glenn- just reread the thread and found that the answer was in a previous post. We're going to hit a couple of quarries today and see what happens.

kath

Good luck kath. I hope you get some. I'm planning to work my way to a total of 1lb/sqft by next Fall. I may even try some on a section of grass and see if I notice any difference.

Glenn