clay-like soil : Aeration?

[Andrews Lawn]

Is aerating the answer to a lawn that is mostly clay? Can you spread sand to help loosen it over the years? What else can you put on it to help it out? I thought I might ask you experienced guys for advice. thanks

[65hoss]

Yes, aerating will help clay. I would never suggest sand. Some will, but not me. Sand and clay make concrete. A good rule of thumb is organic matter. Organic matter will allow the soil organisms to start working, allow earthworms to get active, and give the carbon the grass needs. Organic matter will help the soil to rebuild its topsoil.

[LAWNGODFATHER]

Gypsom

[mac43rn]

won't gypsom decrease the lawns pH?

[stslawncare]

some quality topsoil and aeration

[Bob Minney]

Aerate and topdress with organic compost.

[LAWNGODFATHER]

Originally posted by mac43rn
won't gypsom decrease the lawns pH?

That be Lime

Gypsom breaks down the clay.

[joshua]

gypsum, and aearating is your best bet, don't use any sand that will make matters worse 9 out of 10 times.

[yardmonkey]

A couple of interesting sites I've been looking at:

http://www.dirtdoctor.com

http://www.oldgrowth.org/compost/

http://www.wormdigest.org

Organic matter (compost) seems to be the magic thing to improve any type of soil. Normally sand is not added to clay or clay to sand, in either case just add compost. I have a really good book on organic lawn care - Down to Earth Natural Lawn Care by Dick Raymond. He says he would recommend compost more except that it is too expensive. My city has a compost facility so I can get truckloads for free. If you don't have a compost site in your town, then it could be a good idea to start composting grass clippings, leaves, etc yourself. You could charge people for it. It takes a lot of yard waste to make a little compost.

I have seen it recommended to add 3" of compost and till it in to a depth of 9" to really renovate a lawn. Of course this will raise the ground level by 3" unless dirt is removed. This would probably be a huge and expensive project. Adding 1" and tilling in to a depth of 3" would probably be quite a dramatic improvement and much less of a project. You can always just add some compost to the top of the lawn. As little as 1/4" may be effective, especially if done each year or maybe a couple of times a year. Over time, worms will help to integrate the organic matter into the lawn. I am not yet very experienced in these techniques so others may have more info. A guy around here has just opened a store to sell an organic fertilizer that he is making. The main ingredient is corn meal. This seems to be a magic thing that feeds micro-organisms in the soil and gets the worms working. It seems like it could help to aerate before top-dressing with compost in clay soil. I heard about a garden show where that was recommended. In the absence of compost, it could help to add shredded leaves or grass clippngs to the lawn.

Of course it is helpful to mulch mow (and quite detrimental to bag and remove the clippings). If fertilizer is used, it is better to use organic fertilzer for long-term health of the lawn.

I have also heard of adding gypsom to clay to help loosen it. Don't know much about that. Does it help to just top-dress with it or does it need to be tilled in?

(Just some ideas from a guy who is getting very interested in organic techniques).

[LAWNGODFATHER]

Yes that is good, but top dressing is not always the answer.

Were are talking a defference of over $1000 just for a 10k sq/ft lawn. Maybe more.

But hey if you can sell it, it won't hurt at all.

[vipermanz]

Calcium Sulfate will break up clay soils quite well

[Flipper]

I've lived in georgia for many years, where red clay is all over the place. The best thing to loosen red clay is lime. Thats what people use who have to live with it. :rolleyes:

[LAWNGODFATHER]

Originally posted by vipermanz
Calcium Sulfate will break up clay soils quite well

So what your saying is "Gypsum"(correct spellig this time)?

Calcium Sulfate is Gypsum.

Funny that it is one of the main ingredients of some concrete's will break down clay.

http://mineral.galleries.com/minerals/sulfates/anhydrit/anhydrit.htm

[vipermanz]

yep calcium sulfate is the true term for gypsum, i went out and looked at one of my bags of klaysoft

[HOMER]

I've seen a clay soil conditioner at Wally-World..................never bought any but I wonder what it has in it. Next time I'm there I'll read the ingredients.

[HBFOXJr]

Gypsum causes the small particles of clay to bind together and create fewer large Particles. You can't see the difference but there is a difference. A friend did it with aeration and it really worked quick to eliminate or minimize wet spots.

A so8il wetting agent or surfactant is also a help in getting water and product into the soil including under clay conditions.

[LawnLad]

Well, I think if you ask 10 experts, you'll get 12 opinions. If you listen to the OSU Extension agents here in Ohio, they'll tell you that gypsum with jip 'em. There is little benefit to using it, if any. Further, the quantity that you'll have to use may be prohibitive.

Lime is used to raise the pH. When soil is too acidic, turf grass can't pull certain nutrients from the soil. As well, if the lawn is too basic (over 7.0), some nutrients aren't available. If the soil pH is too high and you're trying to bring it down, use sulfur. It's a catch 22 depending on what micro nutirents you're looking at - no situation is ever going to be ideal. You often have to manage to the situation you have in the residential turf since the budgets don't allow for golf course expectations.

The volume of sand that you would have to add to a clay based yard would make it practically impossible to amend the soil appropriately.

Sand, silt and clay are the three primary components of soil. If you had a volume of soil, the appropriate break down of components would be 45% sand/silt/clay, about 5% organic matter, 25% air and 25% water. These ratios will change according to the site. If you have compacted clay, you will most certainly have less air than desired.

The best thing that you can do is to aerate the lawn frequently and top dress/rake in active organic matter like humus, compost or manure. Sterile organic matter such as peat moss won't do a whole lot for you. If the soil is "active" with the microorganisms, your organic matter will break down in relatively short order. You'll need to top dress again as the soil profile changes. One aeration/top dressing to start may not be enough. You may want to do this spring/fall/spring for example and then monitor from there. It is not cheap, but can be effective.

Turf specialists will also caution you that you do not created perched water tables by topdressing with different kinds of soil. You do not want to create layers of different soil. Therefore, aeration and light topdressing is the preferred method since you'll be incorporating the new soil more gradually. They will tell you to top dress with the same type of soil as the base - however, this isn't always practical. So use some ogranic matter but watch to make sure you're replenshing it as it decomposes.

[ohiolawnguy]

there is a small article in the February 2002 Grounds maintenance magazine that talks about dealing with clay.

you can probably find it online if you dont get that magazine.

grounds-mag.com (http://www.grounds-mag.com)

the article is on page 66, research maintenance/dealing with clay. it is a generalized article, but makes some good points.

[lawnstudent]

The University of Illinois extension agents make the same recommendations here. Gypum is not effective on the clays of the Midwest. It is suppose to be beneficial in southern states where the soils collect salts.

At a minimum, aerate. The aerated holes in the lawn will fill with organic matter from your mowing, incorporating OM into the soil. A light top dressing with organic matter like mushroom compost or a mixture of top soil & OM will also help. Adding organic matter to any soil will improve the structure of that soil over time.