# Manure to compost - how long does it take?



## Tara Brown (Jan 10, 2011)

I will be asking around at local farms to get a lot of manure/compost for our huge garden.

How old should the manure be to till directly into the garden? I will probably be getting cow manure.

Thanks!


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## MaineFarmMom (Dec 29, 2002)

Manure doesn't turn into compost unless you compost it. You'll have aged manure. I compost it to avoid spreading weed seeds.


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## geo in mi (Nov 14, 2008)

USDA ORGANIC rules: The age of the manure itself doesn't matter. It can't be spread earlier than 90 days before planting anything which does not have edible parts coming into contact with it, 120 days for planting anything that has edible parts coming into contact with it. Compost must be turned three times with 160 degree internal temperature reached before each turning--and have a measured 30:1 ratio .......then it can be used. 

Those rules are ultra conservative and are more concerned with pathogens than any other consideration. For fresh cow manure, I would spread directly and immediately, thoroughly till under or plow under maybe six weeks before planting time. You will get some time to allow for decomposition to release Nitrogen into the soil, dilute the salt content from the urine(as well as saving the urea from going up as volitile Nitrogen), and probably kill off any excessive bacteria such as e. Coli. Added time will be allowed as the plants grow before flowering and fruiting.

geo

geo


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## sammyd (Mar 11, 2007)

We don't compost anything, just put the manure down before we till in the spring or fall.


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## frankva (May 21, 2009)

Similar question. If you took 5 yards of horse manure and left it in a pile, how long would it take to cook the seeds that are in it? If ever.


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## Paquebot (May 10, 2002)

frankva said:


> Similar question. If you took 5 yards of horse manure and left it in a pile, how long would it take to cook the seeds that are in it? If ever.


Forever! Temperatures would never get high enough in a simple anaerobic pile. Only proper aerobic composting can get the heat high enough to kill seeds.

Martin


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## MO_cows (Aug 14, 2010)

With a manure pile that is not turned and actually composted, some of it will warm up and cook but most of it will still contain viable seeds. It is still great fertilizer but you have to pull grass/weeds/clover, whatever seeds the animals passed.


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## frankva (May 21, 2009)

About what I figured, but I do appreciate the confirmation.

Now send me some dry weather with sun, please.


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## geo in mi (Nov 14, 2008)

frankva said:


> About what I figured, but I do appreciate the confirmation.
> 
> Now send me some dry weather with sun, please.


As soon as it comes, I'll send you some.

geo


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## sammyd (Mar 11, 2007)

I'll take a few days of that too please...


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