Rob Millar
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The soil at the bottom of a pond for compost?

I know out of a strem this would be a no no, but if I were to use the old silt from a pond would it be too detremental to just dump it on an empty bed that will later be built up?

The customer wants tom use the area for a rockery, and would prefer to not get a skip in to get rid of all the old silt. After wards I was going to add a load of good manure and fertilizer just so it has nutrietns and isnt just empty soil.

The pond has a small feed in from and out to a small stream, but its not moving much water through the pond to wash out the nutrients. The silt is about 2.5 ft deep (just under a metre) and hasnt been cleaned out for a few years. there are lilys in the pond, and a few leaves would have fallen in there over a few years.

Like I say, if it was form the bottom of a stream I wouldnt use it, but I would greatly appreciate any advice.

Many thanks

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Jbest
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If the silt were the same as in my part of the world, I think you would need to add sand and lots of compost. I would not add fertilizer or manure until you do a soil test. Depending on the aquatic life and what is draining into the pond, it may be very high in nitrogen now.

John
Life's Journey is not to arrive at the grave safely in a well preserved body,
but rather to skid in sideways, totally worn out, shouting,
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Rob Millar
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Its thick clay where I am. Thats really really helpful. Thank you Jbest

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smokensqueal
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I would definitely have it tested before trying to do anything with it. If it does test fine for nutrients you still may have your work cut out trying to make it usable for plants. Silt is usually so dense you will need a lot of something to "fluff" it up and allow it to drain.

MagnoliaMan
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TEST! DISCUSS!

The soil from the bottom of a pond may have its cation exchange capacity altered and could be nothing but trouble. Check it out at your local extension service!

Rob Millar
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It is going onto soil already, I was goign to let it dry, dig it in to the soil with some sand and compost, and then just test it with a cheap testing kit form a garden centre. It sound like I should do something more technical, right?

MagnoliaMan
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Test and discuss!

Take a sample to your nearest extension agent and have it tested. Tell them where it came from. Have them explain the changes that soil can go through on the bottom of a pond.
Sand is usually not a good thing to add, but organic material is.

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smokensqueal
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Definitely have it tested. I'm not sure about everywhere else but I found out last year that my extension office only charges a few buck to have it tested. Cheaper then even a cheap test kit.

Rob Millar
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You'll have to forgive me. Im in the U.K, and don't know what an extention office is!

Ive done the job now and its on the customers bed. He's happy regardless of wether it has nutiresnts in it or not, just as long as it doesnt kill anything that goes in there.

The stuff I got out looked and smelt like it could of been good stuff, and a neighbour who has the same stream runing through his garden commented on how it was good for the beds. Hes' not a proffesional gardener and so doesnt really nkow what he was talking about, but I figured that as it was the same area and stream and river bed, maybe there was something in it (forgive my insulence at ignoring everyones advice).

I was going to buy a kit to from a garden centre and see wether it was ok or just empty, and then just fluff it up with compost as the customer is more than hapy to do that and had the idea in the first place so he could use the silt for a new bed.

If it helps, im in a a county called Kent in the South East of England, the ground is very clay-y here.

Many thanks guys

Rob Millar
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Location: England

Again if it helps, There are aload of lily's in the pond, lots of frogs in spring, it is fed from a stream which is about 1 foot (30cm) away. A few leaves from a Tulip tree will fall in there over the course of a year.

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smokensqueal
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Ah I should of seen that. Here in the US we have a government group called Farm bureau which have extension offices for many different services. You may also have something similar there. Otherwise I did find this site that may help [url]https://www.agregister.co.uk/product-404750.html[/url] Or go take a drive out to the country and ask one of the farmers or you might even be able to call up a farm fertilizer supplier and ask them.

A number of years ago I got some "dirt" from a pond/lake someone was digging out. This was before I got into gardening. It did grow some stuff but very difficult to work with. But I'm sure if I would of used compost to mix in with it I would have a different story.

Rob Millar
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Location: England

excellent. Ill ask around.

Thanks for the great advice guys

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