Can you over-apply corn gluten meal as a weed supressant?

bananastandMay 23, 2009

Hi, I'm new here. Not sure where to post this... it's actually probably an "organic landscaping" question, but there is no forum for that I can see. I also x-posted this in organic lawn care.

I decided to replace a large area of lawn around my home with landscaping. It's a sloping hill off the side of my house and was really hard to mow anyway. It's about 1,000 square feet. I planted in lots of native spring ephemerals and native bushes, surrounded by hardwood mulch.

The trouble is, I have silver maple trees along the driveway right next to this area. They drop thousands of propellers in spring, and I found that keeping the area weed and maple seedling-free was nearly impossible by hand.

So I followed the advice posted in another thread on this site, and I went to the feed store to get Corn Gluten Meal as a pre-emergent for weeds. I got a 50 pound bag for just $22. Apparently this product is marketed as Organic Preen and under other brand labels, but it's much more expensive than buying the raw stuff from the feed store. Long story-- Iowa State University accidentally discovered CGM's weed suppressant abilities, and now they license it. Meaning they collect money from products like Organic Preen. Anyway.

So I applied CGM to the area before re-mulching with hardwood bark. I could not tell what setting to put my spreader on. Everyone says it's 20 pounds per 1,000 square feet. I ended up putting the entire 50 pound bag down on my 1,000 square foot area.

Now, the area smells. Really bad. Like something fermenting or rotting or both. Could I have done major damage? Why would it smell that bad? I've done numerous web searches and found nothing. I'm sure the smell is from the CGM. I just hope a bad smell is the only negative... could I be ruining the soil or hurting the plants with this over-application? I wish I had been more careful, but this is what happens when you are working with a product from the feed store that has no label on it to help you know how to spread it.

I guess what I'm trying to say is, please don't berate me for making a dumb mistake... that much I know. If you have helpful info on what I can do to correct any potential problems that might arise, that would be good. I'm also just really curious where the smell is coming from. Does corn ferment when there is too much of it?

Thanks for your thoughts.

Thank you for reporting this comment. Undo

You can over apply anything, and as you have discovered one drawback to using Corn Gluten Meal is that when wet it does have a somewhat disagreeable odor.
Over applying this, like many other products, is not only a waste of your money but can contribute to the pollution we are heaping on our world.

    Bookmark   May 24, 2009 at 6:33AM
Thank you for reporting this comment. Undo

Important to apply at the correct time as a weed suppressant. Too late and you have a very good source of nitrogen but that's about all.

    Bookmark   May 24, 2009 at 8:06PM
Thank you for reporting this comment. Undo
daylilyfanatic4(Zone 6 SE NY)

You may also have a problem with plants not flowering well there do to much nitrogen but no permant damge is done I don't think.

    Bookmark   May 27, 2009 at 7:45AM
Thank you for reporting this comment. Undo

Yeah, probably no permanent damage, but I agree - hoooey! that stuff stinks to high heaven after rain, especially when you overapply. What a surprise, because the dry bags of the stuff in my car made it smell like a bakery. Has anyone else noticed this - they certainly don't warn you. My yard smelled like someone had died.

    Bookmark   May 27, 2009 at 8:11AM
Thank you for reporting this comment. Undo
dchall_san_antonio(8 San Antonio)

Important to apply at the correct time as a weed suppressant. Too late and you have a very good source of nitrogen but that's about all.
You say that like it's a bad thing ;-)

    Bookmark   May 27, 2009 at 10:35AM
Thank you for reporting this comment. Undo

I did apply it when the forsythia was blooming, as directed....

    Bookmark   May 28, 2009 at 11:35AM
Thank you for reporting this comment. Undo
tsugajunkie z5 SE WI

If you go to the Iowa State website there are a slew of papers concerning corn gluten. I read most of them a couple of years ago and as my mature memory recalls 80 pounds per 1,000 sq. feet killed strawberries so it can kill some things. 10 pounds is recommended, 20 would be max strength to use safely.


    Bookmark   May 29, 2009 at 6:05PM
Sign Up to comment
More Discussions
Landscape fabric - safe for organic garden?
I'm planning on building wooden boxes, a la Square...
Broom corn millet-bulk for consumption?
Would anyone know of a source of bulk broom corn seed...
Espoma Organic Tomato Tone - Truly Organic ?
Can anyone tell me if Espoma Organic Tomato Tone is...
Use of Horse manure
Good People- I have access to an unlimited supply of...
Rock salt and asparagus
Someone told me he contols weeds in his asparagus patch...
© 2015 Houzz Inc. Houzz® The new way to design your home™