Do you know what kind of grass you have? Some varieties are more prone to thatch than others.

Do you mulch mow? Many people think that thatch is caused by mulch, but mulch mowing actually helps break down mulch. I think there's a type of zoysia that's an exception to that, but in general, mulching will help get rid of thatch.

Another thing that can contribute to thatch is over fertilizing. Since you've posted this to the organic forum, I think this is less likely to be a problem.

Watering too often can also contribute to thatch, but I'd be surprised if you're overwatering an acre.

A small amount of thatch is actually helpful. I forget the amount, but it's ok to have a little bit.

I wouldn't think you should need to dethatch and aerate. Aeration penetrates the thatch layer. If you leave the cores on the lawn, they'll help to break down the thatch, also.

Do you use synthetic fertilizers (Scotts, Vigoro, etc), or natural fertilizers (soybean meal, corn meal, etc)? I had the same issue a few months ago. The thatch was so thick that the grass was barely growing. I stopped using synthetics, moved to organic and it has helped immensely. I also sprayed down some compost tea, which seemed to help.

The other thing is water -- too much water and too much synthetic fertilizer = a LOT of thatch. The lawn ideally needs 1 inch of water per week. With clay soil it may take a while to get there. I'm currently watering mine twice a week since the clay isn't absorbing the water very well yet.

Oh yeah, and at my local farm & feed store, I found this great thatch rake ($30! Ouch!). I used it in the worst spots to speed the process up, but not the whole yard by any means. I have 1/4 acre and wouldn't rake that whole thing, much less an acre...

"With clay soil it may take a while to get there. I'm currently watering mine twice a week since the clay isn't absorbing the water very well yet."

What I do is water in cycles. I have an automated system, so it's easy for me, but what I do to get 45 minutes of water in one section is to set the timer for 15 minutes, but then I set it to repeat three times. Since I have a 6 station system, that lets each section sit for more than an hour before getting more water. I get no runoff, and the water penetrates deeper.

I have been using Scotts fertilizers up to this point, however I would like to move more to the organic side of things. Can somebody tell me more about soybean meal,corn meal, etc? in regards to when to use which one, how much? etc.? Also.......Habiem where would one buy compost tea? and how is it applied? Sorry everyone I am very new to the organic lawn care thing.

Jlaak, The organic approach is the way to go. Soybean meal is best purchased at farm feed stores. Its an economical way to feed your soil microbes which in turn convert protein to nitrogen feeding your lawn. Try to get as much organic material into your lawn as possible. Mulch mow your grass and leaves. Overdress your lawn with compost. Recycle your paper and kitchen wastes by composting. Soybean meal is a good fertilizer, apply at 20 lbs per 1000 sq.ft of lawn 3 or 4 times a year. Corn meal is used as a fungus preventer/fixer, a very mild fertilizer and a good source of organic material. Use at 20 lbs per 1000 sq ft. as needed for fungus disease issues. Welcome to the forum and good luck with your organic lawn.

If anyone hasn't said it yet, raise your mower to it's highest setting. It will take a few weeks for all of the grass to get that tall, but it will thicken dramatically and help retain water. There are a few types of grass that need to be mowed at the lowest setting, but in WI, I would doubt you have those.

As for compost tea - you make it. It's really easy to make. Fir, you need some compost - I personally buy bagged compost at my nearest Lowes. You're better off making your own compost, but for me that's not an option. I then get a 5 gallon bucket and some 'bubble stones'. They're those little things you see in the bottom of aquariums that bubble to aerate the water. I hook 3 of them up to an air pump (small aquarium type), and put them on the bottom of the bucket. I fill the bucket with 3.5 - 4 gallons of water, and drop in about a gallon worth of compost. Next, and this is critical, you need to add unsulphered molasses. You can get this at any grocery store. I put in a few oz's of the stuff. It's critical because it feeds the little microbes in the compost and helps them to multiple. Turn on the air filter and let it brew for about 24 hours. You'll need to stir it a few times. You'll know it's done because it will have a sweet, earthy smell.

You'll need to strain it into another bucket by pouring it through pantyhose or something similar. Just need small enough holes to catch the big chunks that would clog up your sprayer (I just use a regular pressurized tank sprayer. If you have one you've used with chemicals, I'd get a new one, or clean the old one out REALLY well).

I personally cut this with another 5 gallons of water to make about 10 gallons to spray on my 1/4 acre lot. You could cut it further for your acre, or just brew a little more.

I know it sounds like a big pain at first, but it's really not. Well, at least not after the first batch you make. I will say that it seemed to help my thatch issue improve fairly quickly.

Get soybean meal or corn meal, whatever is cheaper in your area. I pay about $8/bag for a 50lb bag of soybean meal and use about 3 of them on my lawn. Unlike the scotts method, there is no 'right' time to put down soybean or corn meal - just whenever you think the lawn needs it. I tend to put down soybean meal every few months, but I insist on a dark green, lush lawn. If you notice any sort of fungus problems, corn meal is great for that. Additionally, you can put down corn gluten meal in late fall and/or late winter/early spring as it helps prevent seeds from germinating, thereby preventing weeds. Avoid this if you intend to overseed though, as it will prevent those seeds from germinating, too...

Hope this helps!

BPGreen: What I do is water in cycles. I have an automated system, so it's easy for me, but what I do to get 45 minutes of water in one section is to set the timer for 15 minutes, but then I set it to repeat three times...

BP: great idea. My clay soil makes water run off before too long. I just got a new sprinkler controller last year and it will do up to 4 start times. Your way makes a lot of sense to me, especially since the rotors need more than an hour per zone to get the proper water amt.

Thanks to everyone for the input. I am very new to organic lawn care and have learned so much from all of you! The only problem I am having, and perhaps I am looking in the wrong places but I cannot seem to find anyone that carries soybean or corn meal.

habiem.......thanks so much for the compost tea idea. I cannot wait to give it a try.

Subywu--I've found that my soil absorbs water much better now than it used to. I think it's a combination of using more organics and doing the deep watering in cycles. I think part of that is that the deeper water encourages deeper roots, which break up the soil and also put more organic matter there when they die.

I think the key to making the cycle approach work is to make sure the cycles start at least an hour apart, so the water has time to soak in really well.

I'm worse than Habiem and demand a lawn that's perfectly dark green and glowing with health at all times during the growing season. I feed organically once a month, just in lighter amounts, to keep the bacteria and grass happy. That requires a total of 80 lbs per thousand square feet of organics per season. Or more.

I have absolutely no thatch because of the organic feeding. The bacteria attack any thatch that even thinks about starting to build up. Truth be told, I'd like a thin layer for the mulching/water retention capabilities, but that's not in the cards. Even on KBG.

I'm not generally a fan of compost tea--except in this instance. It's certainly going to help reduce the thatch issue you have by injecting bacteria directly into the thatch layer.

Free coffee grounds from Starbuck's (you don't need to buy anything, they're happy you want them because they don't have to pay to discard them) work just fine, but getting enough to do a lot your size would be a bit of a nightmare. Still, it's a good, extra kick of organics at very low cost.

If soybean meal is hard for you to get, try your local bulk pet food store. Alfalfa-based meals are common for gerbils and rabbits, and both will go through a broadcast spreader. They may also carry cracked corn (for feeding deer). That stuff is generally cheap even there. Soy's tougher to get there but sometimes you can manage.

They're more expensive that way, and alfalfa (at 3-1-2 or so) is not as good as soybean meal (at 7-1-2 or so) at feeding the lawn and providing nitrogen.

Either is going to feed your bacteria, get them jump-started, and start eating away at that thatch layer. Both provide organics for water retention, soil loosening, and aeration (from the active bacteria). You can apply either at any time, and 2 times a year up to once a month during the growing season.

Barring that, Milorganite from your local big-box store is workable, if not perfect. It's organic (some argue it isn't, but what isn't processed somewhat these days?), feeds the bacteria, won't burn, and supplies a lot of iron for a green lawn. The analysis is 6-2-0 with 4% iron, and won't burn. 40 lbs usually runs around $9 around here, competitive with 50 lbs of soybean meal and much cheaper than alfalfa ($24 per 50 lbs locally for some reason).

I alternate Milorganite with soybean meal, plus alfalfa going down twice a year.

In last place, because of the price, are organics like Espoma or Ringers. Both work well, but both cost a fortune. I won't use them on my 7,000 square foot lawn because of the price--your size would cost a fortune.

If you're curious, my schedule is:

After Green-up (mid April-ish): Alfalfa, 10 lbs/K sq ft
May 15: Milorganite, 10 lbs/K
June 15: Soy, 14 lbs/K
July 15: Milorganite, 10 lbs/K
August 15: Soy, 14 lbs/K
September 15: Alfalfa, 15 lbs/K
Top Growth Ceases (late October or so): Winterizer, recommended rate on the bag.

By October it's too cold for organics to decay. I'm forced to winterize with (gremble) Scott's.

That schedule is very, very, very aggressive.

Sorry for the silly question, however is this the same soybean meal that can be purchased at the local feed mill? And also, how do I determine the setting of my scotts broadcast spreader?........

Yes, it's the same soybean meal that can be purchased at a feed mill. I don't know how to set the spreader, though. I've got an offbrand, anyway, so it's always trial and error for me.

The setting for your spreader is Wide Open. Purchase enough to spread 15 to 20 lbs per 1000 sq ft. That will seem like a very heavy application compaired to chemical fertilizer. You may have to shake the spreader a little to get soybean meal to flow real well. Make two passes, North/South then East West. Use it all up on your lawn.

Wide open would work just fine!

I have a Scott's Standard broadcast spreader and tend to put it at 5 on the dial (maximum of, I think, 12). I then make two passes in opposing directions to get even coverage.

It's not that important with organics, but I like the idea that every square foot is being fed the same. You could do it by hand and have food fights with people if you wanted to. It's not going to do any harm.

One last question regarding soybean meal. will this green up my lawn like a synthetic fertilizer? Correct me if I am wrong,but the N is what greens up the lawn and compared to synthetics, soybean meal has a much lower N ratio......please help me understand.

Yes, the N is what turns it green. Iron also contributes to that.

And, yes, the soybean meal will darken it up. A LOT!! The thing to keep in mind is that it will take about 3 weeks to really see the result of the soybean meal. The reason is that it will take about that long for the microbes in the soil to process it. I'm somewhat new to this, and not a biologist or chemist, but I believe that the protein is a big factor as well, as it gets converted to nitrogen by the little microscopic guys. I don't know exactly why it works, but it does :)

If you put down around 15lbs per 1,000sq ft, your lawn will turn the darkest, most beautiful green you've ever seen.

This is my first year on all organics and my father recently commented that he was going to try using this 'stuff' I've been putting on the lawn, because I have the thickest, darkest green lawn he's ever seen. One of my wife's friends asked who we pay to get our lawn looking this great.

I was completely amazed at what the soybean meal did for my lawn.

It greens up the lawn, but in a different way. The N is only available after microbes digest thee SBM, so it is slow release, and it only works when the soil is more than 40 degrees F.

If it has half the N of the synthetic you've been using, then to get the same amount of N, use twice the amount of SBM as you did of the synthetic to get the same amount of N.

habiem, This information is provided by a frequent poster here.

Here is a link that might be useful: Organic lawn FAQ

Sorry, I meant to address jlaak with the FAQ

Once again, thanks for all the helpful info..........Since I have an existing thatch problem,when I apply the SBM will the it be able to penetrate the thatch to start working the soil?

Since I have an existing thatch problem,when I apply the SBM will the it be able to penetrate the thatch to start working the soil?

Yes and no. Decay will start in the thatch layer since the bits of soybean are kinda big, but it'll filter down to the soil surface and keep working there.

That's a good thing. The decaying soybean will host bacteria and fungi which will happily eat the thatch layer, too.

I realize that this post is very very old, but have been reading these forums for a year plus but have never joined. Really appreciate the help everyone has provided regarding thatch, etc. Not sure if anyone who posted here is still around, but I'm basically following my own program similar to the one morpheuspa posted above. My question is regarding if I use the Scotts winterguard, will that kill the microbes, etc that I have worked so hard to get back into the yard to get rid of the thatch? Also, some people say that winterizing is unnecessary, but I believe it should be useful in helping to prepare for the harsh winter and also recover from it. Thank you in advance to anyone who helps out!

Some thatch in turf grass is beneficial (1/2 inch). Thatch in turf grass can be controlled if the soil has an active Soil Food Web, ie a good healthy soil. Synthetic fertilizers tend to be harmful to the Soil Food Web and any product from that company will tend to kill off the beneficial microbes.
"Winterizing" lawns is a term made up by the sellers of synthetic fertilizers to promote more sales, although feeding the turf grass in the fall so they can get ready for growth next spring does make sense. What is needed, besides a good healthy soil, may be a food source with limited amounts of Nitrogen, something with less then 10 percent N since much more then that simply gets washed out of the soil and causes pollution of the ground water.

Here is a link that might be useful: About thatch in turf

kimmsr, What do you recommend then? Ive been using ucg and milorganite along with mulching the grass when mowing. I also started mulching the leaves in last year. I believe the thatch is getting under control from not using any synthetic fertilizers and following what I have done above.

Keep in mind that it can take 3 to 5 years before you really see the results of working to create a good healthy ecosystem for your grass to grow in, so patience is necessary.
If you are concerned about the thatch, dig in and look at how much is there. Knowing is always better then guessing. If you have not had a good reliable soil test done, for soil pH and major nutrients, now is a good time to do that and then these simple soil tests,
1) Soil test for organic matter. From that soil sample put enough of the rest to make a 4 inch level in a clear 1 quart jar, with a tight fitting lid. Fill that jar with water and replace the lid, tightly. Shake the jar vigorously and then let it stand for 24 hours. Your soil will settle out according to soil particle size and weight. For example, a good loam will have about 1-3/4 inch (about 45%) of sand on the bottom. about 1 inch (about 25%) of silt next, about 1 inch (25%) of clay above that, and about 1/4 inch (about 5%) of organic matter on the top.

2) Drainage. Dig a hole 1 foot square and 1 foot deep and fill that with water. After that water drains away refill the hole with more water and time how long it takes that to drain away. Anything less than 2 hours and your soil drains’ too quickly and needs more organic matter to slow that drainage down. Anything over 6 hours and the soil drains too slowly and needs lots of organic matter to speed it up.

3) Tilth. Take a handful of your slightly damp soil and squeeze it tightly. When the pressure is released the soil should hold together in that clump, but when poked with a finger that clump should fall apart.

4) Smell. What does your soil smell like? A pleasant, rich earthy odor? Putrid, offensive, repugnant odor? The more organic matter in your soil the more active the soil bacteria will be and the nicer your soil will smell.

5) Life. How many earthworms per shovel full were there? 5 or more indicates a pretty healthy soil. Fewer than 5, according to the Natural Resources Conservation Service, indicates a soil that is not healthy.

may be of some help as well.

kimmsr, thanks for the response again, those are definitely other factors to consider, and I make have to look into those, but the lawn is pretty healthy right now and I think after the past two years or so of no chemicals, using the ucg and milorganite that I can tell a difference. Do you have any suggestions on anything that needs to be put down before winter? I just put milorganite down around maybe a month or so ago, and put quite a bit of ucg on a section every week.

The Milorganite and coffee grounds should be ample.