How to mitigate compost being too "hot"?

mbat(6)April 7, 2014

I gave some compost to a friend last year, who found that it "burned" his beans and was too "hot". I am using it this year and wondered if by spreading it over the garden last winter, that might mitigate the "heat"?

Thank you for reporting this comment. Undo
toxcrusadr(Zone 6a - MO)

It was probably not completely decomposed and was either anaerobic or too high in available N. After sitting all winter this should not be a problem anymore.

    Bookmark   April 7, 2014 at 6:10PM
Thank you for reporting this comment. Undo

I suspect it will but what exactly do you mean by "spreading it over"? Was it worked into the soil at all or left like mulch on top.

Phytotoxicity from compost and organic materials can be a result of several different factors. More time for compost to cure is one way to alleviate one issue. There may be others.


    Bookmark   April 7, 2014 at 9:37PM
Thank you for reporting this comment. Undo

I don't believe regular compost can supply a harmful level of N and burn plants. I have always promoted organic over bagged fertilizer to avoid over feeding by inexperienced gardeners. I suspect your friend had a disease,insect or somthing and just blamed it on the compost because he wasn't sure what happened to the beans.

    Bookmark   April 9, 2014 at 2:25AM
Thank you for reporting this comment. Undo

Finished compost will never be "hot" enough to "burn" plants. But unfinished compost might. The way to mitigate problems in the future is to use only finished compost.

    Bookmark   April 10, 2014 at 6:42AM
Thank you for reporting this comment. Undo

Thanks for all of these thoughts and suggestions. Having "thought" again about the quality of the "compost", I have to say that it was more like animal manure mixed in with vermiculite that had sat around for a couple years. So maybe it was still a little too "live" for the beans?

And as to "spreading it all over", I distributed bags of the stuff over many parts of the garden, but did not bother to spread it out completely. But it has been sitting there since October.

Thanks for your input so far.

    Bookmark   April 10, 2014 at 8:03AM
Thank you for reporting this comment. Undo
toxcrusadr(Zone 6a - MO)

If the manure has aged for a couple years, I can't imagine it burning any plants. That's finished compost. It must have been something else that damaged those beans. Did your friend say what they actually looked like?

    Bookmark   April 10, 2014 at 1:20PM
Thank you for reporting this comment. Undo

I am wondering the same, worried about burning my veggies w manure. Rather than do a new post, I will describe my situation. I am moving my garden location some to make room for a garden shed. I have just picked up about 2 yards of aged horse manure from local stable that cleaned up 3 years of manure. The manure is mostly well aged, like a 30 mph wind would just blow it away, there is some fresh mixed into the pile.

I will put the fresh manure onto my compost heap to get it cooking. The dry aged manure I want to spread a light layer onto my yard of fescue grass and fruit and shade trees. But, most of the dry aged manure I want to import into the "new" part of the garden which got rototilled a month ago . The new garden area is abit low in elevation, so my thinking is to spread the dry manure onto where I want my veggie beds to be and rototill that w my new electric tiller I just got from amazon. Then, I will import about 4-6 inches of the incredible black worm filled soil from my old garden where I want to build my 10x20 shed (as it would be a waste of rich soil to build on the topsoil and also would not be structural), . I will rototill the 4-6 inches of rich dirt into the new garden area lightly so the manure is mostly 6 inches below the final grade w the good garden dirt on top. Hoping that I can then plant my starts next week without burning them if the bulk of the manure is below the final grade 4-6 inches deep. I also have flood irrigation every 5 days and the entire yard/garden goes under water, so that will probably help to break the manure down quicker or it might release nitrogen and burn my plants???? I am hoping the water will just make a nice compost tea of the manure and get the plants a nice nutritional drink every 5 days?? Never used manure before, always made my own compost and added some amendments. I am in Moab, UT at 4000 ft w last frost date of April 15. Any insight here as I am worried I might wipe out my garden if the manure is too "hot".

Also, I am worried about importing weed seed from the manure into my garden, so I am thinking that burying it 6" deep will keep the seeds from germinating and they will get broken down by natural processes by the end of summer?? thx so much. Any thoughts or advice on my plan??

    Bookmark   April 10, 2014 at 4:05PM
Thank you for reporting this comment. Undo
toxcrusadr(Zone 6a - MO)

I think you will be OK with that plan. It all depends on how confident you are that what you think is 'aged' manure actually is. One way to tell is to wet a shovel full of it, get it good and damp, and smell it. If it smells like compost, it is. In which case it will not burn plants no matter what the depth.

As for seeds, some can survive a long time in the ground and sprout when they're brought back up into the sun. I've heard that cows digest seeds better than horses, so horse manure has more viable seeds in it. Hot composting can kill more of them than cold. If I could get manure, I don't think I'd care that much which kind, I'd deal with it.

    Bookmark   April 11, 2014 at 12:38PM
Sign Up to comment
More Discussions
Clay, silt, and sand layers - failure
I've done the "mason jar" test (following...
Composting gone cold
I've been composting for decades, but this winter,...
starting a new nursery/retail landscape supply business
lots of good reading here. I am looking at starting...
Need advice on watering succulents with new soil
I recently began using soil-less soil, as has been...
Questions about gritty mix
Hi folks, I am a long time gardener but new to the...
hsw (zone 6, Boston area)
Sponsored Products
Paley Leather Chair - Brighton Soul White White
Joybird Furniture
Home Decorators Accent Rug: Antoinette Wembley Black/Beige 2' 6" x 4' 6"
Home Depot
Honey Pendant by Tech-Tiella Lighting
$156.00 | Lumens
Kartell | Taj Mini LED Table Lamp - Quick Ship
$280.00 | YLighting
Compression Basin Faucet
Signature Hardware
Madras Dyed Rug 9' x 12' - BLUE
$6,499.00 | Horchow
Lenox Winter Greetings Glass Cheeseboard with Spreader
Signature Lily Pendant Small - Zinnia Glass with Nickel Hardware
$441.00 | Bellacor
© 2015 Houzz Inc. Houzz® The new way to design your home™