How do i know when manure is well rotted?

heno55

hi to everyone i have a few trailer loads of horse manure and i am wondering how best to use it, all the gardening books say to use well rotted manure but how do i know when it is well rotted and if its not and i dig it in anyway am i going to have problems, i know that it will cause forking in carrots but what other problems will it cause

James Kilkelly · Posted: Thu Jan 27, 2011 2:57 pm Post subject:

As a rule of thumb, well-rotted manure/compost will be over six months old, and tend to be dark brown with little if any smell. You should not be able to distinguish individual pieces of straw, hay, vegetable peelings, grass etc., as it will all be rotted down.

walltoall · Last edited by walltoall on Fri Jan 28, 2011 8:05 am; edited 1 time in total

May I add a finger to James's rule of thumb. Along with all James says well-rotted manure will be dry. If you squeeze a handful of well rotted manure tightly, then open your hand and shake away the sample, your hand may be a little soiled but it will be DRY.

tippben · Posted: Thu Jan 27, 2011 10:12 pm Post subject:

Does it still look more like poo than soil? Best to cover it so the nutrients don't leach out, and wait, or load it into plastic bags, tie the top, and have another look in late may/june. If it is blackish and crumbly, it's good for mulch, or digging in. In between? I'd dig it in- you still have 2 or 3 months before things will be planted, and it will decompose quicker in the soil.

As far as adverse effects go, fresh manure is very high in nitrogen. This can scorch plant roots if they come in to direct contact with it. Also, it can promote lots of fresh leafy growth, which is very susceptible to frost and sap sucking insect damage. Plants like courgette, nasturtium and beans may produce lots of leaves at the expense or flowers and fruit. There is also the potential of growth hormones, antibiotics, and pesticides being present, which could end up present in your food. Not proven health implications, as far as I know, but possible.

The only common veg plants I'm aware of that actively dislike freshly manured ground are the onion family and the carrot family. If it's still a bit fresh and you can't store it, dig it in where you're going to grow spuds. They can take nearly anything, and act as a "cleaning crop" due to the thick leaf cover- any weeds in the manure should be shaded out.

Nozebleed · Posted: Thu Jan 27, 2011 10:27 pm Post subject:

I manured (well rotted shop bought)a plot during the winter which i now intend on using for onions,leeks & shallots..i didn;t know they disliked manure..will i have to change my plans?

tippben · Posted: Fri Jan 28, 2011 3:10 am Post subject:

No, you should be ok nozebleed. It's freshly manured ground that is not recommended (Ie: within the last three months, or with partially rotted stuff). Your stuff should be more like compost, and with the exception of garlic, sets needn't go in for another month, and leeks not until april/may. Also, in a new plot, I reckon soil enrichment is vital for structure- I'd manure anyway, and just put up with a possibly poorer yield for the sake of better crops in years to come. Mine are all going in a new raised bed enriched with old tomato growbags from the polytunnel, plus homemade compost. I'll manure it next autumn.

heno55 · Posted: Mon Jan 31, 2011 7:27 pm Post subject:

hi all thanks for the replies they are a great help,the manure still has a very strong smell of urine so i guess i will just leave it for the autumn although i might dig some in where the spuds are going, as for the pesticides and antibiotics that would apply more to cattle manure what i have is horse manure.