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Author Topic: clay soil amendments?  (Read 520 times)

brian

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clay soil amendments?
« on: September 10, 2017, 10:01:18 AM »
As my greenhouse construction progresses I'm starting to think about soil.   I intend to plant trees directly into the ground inside my greenhouse.  My soil is clay but not too hard - the topsoil crumbles under hand pressure.  The dirt on my greenhouse floor is loose right now because it is recently excavated from the foundation trench.   I have an opportunity now to amend it, and/or shape it to affect drainage.   Any suggestions? 
  • Doing nothing at all may be a viable option.  The clay drains poorly, but as I will have full control over how much water goes inside, I'm not sure if this is a real concern or not.   
  • Mix in a large amount of mulch or some other organic matter and roto-till it in?  The greenhouse is 18'x32' so it would take ~10cu yds to fill 6in deep. 
  • Mix in a large amount of perlite or sand to improve drainage?  But it would still be clay underneath so unless I shaped it to drain to the edges I don't see it making a difference other than perhaps improving root penetration.   Also I read that adding sand to clay is a bad idea unless you add a massive amount of sand. 
  • Just add mulch on top, and renew every year or two and let it works its way down over time. 
  • Create mounds or rows and plant trees there, perhaps with amended soil or 4x4 wood boxes to create "raised beds" that drain to the sides

Lauren08

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Re: clay soil amendments?
« Reply #1 on: September 10, 2017, 11:32:49 AM »
Hello
In a garden center near me in nc they have something called perma till. Im not sure of its price but i hear its a awesome soil ammendment. Its made of lava rock or sonething of the sort (i think) and it never degrades so you never have to replace it. I dont know of its what you have in mind but its a thought. You can also get bags of soil conditioner. Its like mulch

mrtexas

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Re: clay soil amendments?
« Reply #2 on: September 10, 2017, 11:36:54 AM »
As my greenhouse construction progresses I'm starting to think about soil.   I intend to plant trees directly into the ground inside my greenhouse.  My soil is clay but not too hard - the topsoil crumbles under hand pressure.  The dirt on my greenhouse floor is loose right now because it is recently excavated from the foundation trench.   I have an opportunity now to amend it, and/or shape it to affect drainage.   Any suggestions? 
  • Doing nothing at all may be a viable option.  The clay drains poorly, but as I will have full control over how much water goes inside, I'm not sure if this is a real concern or not.   
  • Mix in a large amount of mulch or some other organic matter and roto-till it in?  The greenhouse is 18'x32' so it would take ~10cu yds to fill 6in deep. 
  • Mix in a large amount of perlite or sand to improve drainage?  But it would still be clay underneath so unless I shaped it to drain to the edges I don't see it making a difference other than perhaps improving root penetration.   Also I read that adding sand to clay is a bad idea unless you add a massive amount of sand. 
  • Just add mulch on top, and renew every year or two and let it works its way down over time. 
  • Create mounds or rows and plant trees there, perhaps with amended soil or 4x4 wood boxes to create "raised beds" that drain to the sides
Don't amend clay soil. You will create a bathtub to drown your plants. Make a raised bed. Soil here is 100% clay, dig it up and fire into bricks.

Millet

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Re: clay soil amendments?
« Reply #3 on: September 10, 2017, 11:43:23 AM »
Raised beds is the best option.  Further, trees on trifoliate orange do good on clay soil and are also rated as good for wet soil.

Susanne42

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Re: clay soil amendments?
« Reply #4 on: September 10, 2017, 02:30:48 PM »
Michigan has a lot of clay, and areas with no clay seem to be silt, equally bad I think. There is a big green house near where I live and they have a huge grapefruit tree in there. i have not figured out yet if the container it is in, is bottomless or not but think for places with unfit soil it would be a good solution?







brian

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Re: clay soil amendments?
« Reply #5 on: September 10, 2017, 07:43:34 PM »
Mrtexas I totally agree with you on the bathtub effect - I definitely don't want free-draining depressions in the clay that will pool water.   However, I'm thinking if I graded the clay so it flows to the edges, then possibly put better soil on top for anywhere from a few inches to ~2ft, I should get the best of both worlds.  The "permatill" expanded-rock that Lauren mentioned looks similar to perlite... would help with drainage though I'd need a ton of it. 

Also, as Millet mentioned some trees will be fine with clay, however I'm not sure what the rootstock is on most of mine, and I also intend to grow some other tropicals - not sure how well they will handle clay. 

Here's a few of the ideas I have so far.  If I did a raised-bed-per-tree I could maybe use the existing 200ft of rootmaker material I have now and make 3-4ft diameter bottomless pots out of it. 




« Last Edit: September 10, 2017, 08:34:55 PM by brian »

Millet

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Re: clay soil amendments?
« Reply #6 on: September 10, 2017, 09:39:46 PM »
In my greenhouse I have a Dekopon and a Cara Cara growing in raised beds.  The Cara Cara has been planted in the bed a long time .  The tree is now 11 feet tall and 11 ft. wide, so I'm sure the roots have long ago grown into the hard pan soil under the raised bed.   For another citrus tree, I originally dug a hole 4-ft. wide X 4-ft. long X 4-ft. deep in the hard pan (took forever), and filled it with a good soil mixture.  It is also doing good.  The other 5 in ground trees I just planted directly into the ground, and they have grown to be large trees.  So there you have it, I did a lot of the original work, that perhaps I did not need to do.

brian

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Re: clay soil amendments?
« Reply #7 on: September 10, 2017, 09:57:22 PM »
Millet, that is encouraging.  Perhaps the easy way is the right way to go here.  That would be a nice change of pace for me. 

AnnonaMangoLord45

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Re: clay soil amendments?
« Reply #8 on: September 11, 2017, 12:14:34 AM »
Please don't use organic matter. Use sandy loam instead, pure sand, silt, and clay. Only dress compost on the top.

brian

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Re: clay soil amendments?
« Reply #9 on: November 27, 2017, 04:26:57 PM »
I did a quick water & soil test.

One soil test was for 'slaking'.   Put a few tiny (2-3mm) dirt clumps into water and see if they retain their shape for 5min.   Mine did not, they pretty much instantly puffed up and flattened out.  This is bad, meaning they soil won't retain air pockets.

The other test was for ph and total alkalinity.
For plain water (city water), the left samples show ph of 7.0, and Total Alkalinity at ~80ppm.  Not bad.
For the soil, I stirred up a bunch of soil and water, then let it settle and measured the water.  Right samples show ph around 6.8 and Total Alkalinity around ... 0?  This makes no sense to me.  How could adding soil reduce total alkalinity?  Isn't it an absolute measurement?   I thought maybe I was getting soil bits on the test sample so I did a bunch of them.  All same result.   



Millet

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Re: clay soil amendments?
« Reply #10 on: November 27, 2017, 10:02:46 PM »
Suggested OK levels for total alkalinity is 0 - 100   My well water was 188.3 MG/l.   Over time that level of alkalinity REALLY bothered by trees, and even begun stunting the growth. .  I switch to rain water, and in no time all alkalinity problems disappeared.  I've been irrigating with rain water now for 13 years (since 10/18/04).  Ideal pH for citrus is 6.5, but a Ph of 7 would absolutely be no problem.  Many citrus even do OK at a Ph of 8.   If you want to grow citrus in ground the sodium level should also be tested.  A  level of 50 MG/L or less is OK.  Rootstocks that are rated as GOOD for clay soils are, Trifoliate Orange, Cleopatra mandarin, Sun Chu Sha mandarin, Shekwasha mandarin, Cleo X639, Sour orange, Smooth Flat Seville, and Kinkoji,   Rootstocks rated poor for clay soils are Swingle, Carrizo, Benton citrange, C-32 & 35.  All of my trees are growing on Flying Dragon, and they all do very well in my clay soil..  If you wish to do something to counter act the clay soils,I would think raised beds would be the easiest solution. As I wrote in an earlier  post I used raised beds, also dug a really big hole 4' x' 4' x 4'  filled with quality soil, and lastly did nothing for 4 of my in ground citrus trees.  There was no difference between any of them.

brian

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Re: clay soil amendments?
« Reply #11 on: November 28, 2017, 04:24:46 PM »
Thanks Millet.   I'd *like* to just plant trees directly in the dirt with no amendment, as its the easiest, but I am worried they will become starved for oxygen.  I am thinking of putting a couple in the ground now as a test.   

I will likely send off soil and water samples to the Penn State agriculture office for testing, but I was pleasantly suprised that my city water appears significantly better for growing than the well water at my old place. 

One issue I have now is that I have no idea what the rootstock is for the vast majority of my trees.   Most of them don't say.  The calomondins, meyer lemons, and persian limes all look to be grown from cuttings.   I expect most of the fourwinds trees are on Cuban Shaddock.  I may just graft my favorite varieties onto trifoliate orange planted in the dirt, and see if they overtake the containerized ones in growth.

Citradia

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Re: clay soil amendments?
« Reply #12 on: November 28, 2017, 07:47:20 PM »
Most of my soil is sandy loam with some pockets of red clay. However, around my house where I have a garden, it is hard pan like concrete almost. I have a French drain around foundation of house with gravel up to surface. I've found that instead of digging holes and putting amended soil in them with plants/shrubs/ citrus, they all do better when I dug out all of the old hard soil ( it's even grey white like concrete) and replaced it with new top soil mixed with garden soil ( bagged), the plants do great and figured the French drain helps drainage. Citrus have shallow roots, so I figured they would do good sitting in a foot or so of god top soil with hard pan underneath. My grandparents citrus trees in Palmetto, FL were twenty feet tall and full of fruit, on shallow sandy black soil with hard pan about a foot or two down. I like your plan with new soil on top of sloped graded virgin soil draining down to sides of building.

Mark in Texas

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Re: clay soil amendments?
« Reply #13 on: December 06, 2017, 07:43:01 AM »
Am surprised Philip (Mr. Texas) and Millet didn't mention my method.  Am fruiting avocado, mango, citrus trees using RootBuilder pots.  They do root into native clay loam after enjoying the potting soil.  Some are quite large and being topped at 10'.  http://tropicalfruitforum.com/index.php?topic=7511.msg96609#msg96609
« Last Edit: December 06, 2017, 07:45:18 AM by Mark in Texas »

brian

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Re: clay soil amendments?
« Reply #14 on: December 06, 2017, 01:37:14 PM »
I think we did discuss that here actually.  I already have 200ft of rootmaker so its an easy option.  I'd have to switch to a gritty mix that never requires changing.  Right now I'm using a mulch mix that requires yearly replacement. 

EDIT - oh wait we talked about it in the greenhouse planning thread http://tropicalfruitforum.com/index.php?topic=18512.100
« Last Edit: December 06, 2017, 01:53:51 PM by brian »

Millet

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Re: clay soil amendments?
« Reply #15 on: December 06, 2017, 03:11:22 PM »
Mark, I actually have a Saint Dominic Sour Orange tree planted from seed. When it was large enough the tree was transplanted into in a large bottomless Root Maker container.  It has been growing in the container for 5 or 6 years and has long ago rooted into the ground.  The tree is doing fine with nice fruit on it.
« Last Edit: December 06, 2017, 09:44:52 PM by Millet »

Mark in Texas

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Re: clay soil amendments?
« Reply #16 on: December 08, 2017, 09:53:52 AM »
Mark, I actually have a Saint Dominic Sour Orange tree planted from seed. When it was large enough the tree was transplanted into in a large bottomless Root Maker container.  It has been growing in the container for 5 or 6 years and has long ago rooted into the ground.  The tree is doing fine with nice fruit on it.

Too cool.  I need to buy another roll to expand a Frankancado.  Millet, one thing I've noticed is that unless you use at least 4 or more cable ties, they break on large pots after a few years.  I've learned to wrap one piece of 24 ga. galv. wire around the middle, pull the ends tightly together and twist the ends with my hands and then heavy duty ranch pliers.  BTW, I've added organics like peat, compost, pine and cypress bark to my mixes and have no issues.

Stay warm......

 

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