Feed Your Soil for Free While Helping a Horse Rancher




Introduction: Feed Your Soil for Free While Helping a Horse Rancher

Garden soils need organic matter to hold moisture, slowly release nutrients, add to soil tilth so roots can be cozy and get at soil particles... There are lots of horse stables and pastures where I live in N. Central Florida, as well as high temperatures which lead to fast decomposition of organic matter in these sandy well-drained soils, so my garden needs a healthy - pow! - shot of nutritious organic matter every fall.

Horse farmers have huge piles of free horse manure, urine and straw that get cleaned out of stables that can get them in trouble with the department of environmental protection because of the nitrogen that can leach out and go to creeks and streams in heavy rains.  USDA or state agents go on visits to farms to see how their poop piles are doing, and the smaller they are the better.

This instructable tells you how to
1. find free fresh horse manure
2. get it to your house
3. add it to your soil as a mulch, or as a soil amendment for future plants.

You will need:
1. station wagon OR pickup truck with some big tarps
2. a few shovels
3. a hearty friend who likes poop
4. recycle bins or wheelbarrow

Concerns: We see a lot of mold colonies in the poop and when you move it around, lots of spores go flying. Also, some broadleaf herbicides may have been used on the hay the horses ate which stay intact going through the horse and could damage some plants in your garden. While it doesn't hurt to use gloves, it's good to know that horse manure has lower risks of bacterial/viral infections from E. Coli, Salmonella, Giardia, Crypotsporidium and other diseases compared to other animal poops including cows, poultry, pigs and dogs (see study).

Found this here about why organic matter in soil is great:
• Improves tilth, condition, and structure of soil, providing better aeration and temperatures.
• Supports living soil-organisms.
• Improves ability of soil to hold water and nutrients.
• Helps dissolve mineral form of nutrients.
• Buffers soil from chemical imbalances.
• Maintains a steady supply of plant nutrients.
• Helps recycle organic wastes, thus keeping them out of landfills and waterways.
• Replaces manufactured nitrogen which requires energy to create in a factory and ship around.

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Step 1: Find a Horse Boarding Stable

The best bet is to find a horse boarding stable, as they have lots of horse owners coming in and out... call or drive up and ask if they have some manure they'd like to get rid of. You'd be willing to remove their waste problems for free. If you're lucky, you'll find some composted manure. (Some pay to have it hauled to a landfill, or spend energy and tractor time composting it.)

A 1000-lb horse creates 50 lbs of poop and pee per day!

Step 2: Get the Poop

Drive your pickup or station wagon full of empty recyble bins up to the horse manure pile. Find the part of the pile that has the most composted manure (it is the darkest!)

Line the pickup with a big tarp. Start shoveling it in!

When you have all you want, cover it with a tarp and throw shovels on top.

Step 3: Mulch Some Plants

This partially decomposed horse manure has a very high Carbon (C) to Nitrogen (N) ratio because there is a lot of straw (high carbon) mixed with the manure and urine (high nitrogen). Microbes reproduce and build themselves out of carbon and nitrogen, so if there is a high carbon content relative to nitrogen, microbes will take advantage of all that carbon and eat all the nitrogen they can get to make more of themselves.  A microbe cell C:N ratio is around 25:1.  So if your poop has a C:N ration higher than this (it's typical for manure with bedding to have C:N ratio > 30:1), there will be no nitrogen available to plant roots.

If you use cow manure from a dairy or feedlot, the C:N ratio will be much lower.

This means that if you mix this partially decomposed manure into the soil and put in plants right away, the plant roots might get some phosphorus and potassium, but there won't be any nitrogen for them to take up because the microbes will be eating it all so they'll turn yellow being starved for N! 

Use the recycle bins or wheelbarrow to move your mulch from vehicle to garden.

You can mulch plants by putting the partially decomposed manure on TOP of the soil. Here it will serve to contain moisture in soil and keep cold freezes from hurting roots.  As the manure decomposes, nutrients will go down into the soil and feed the plants over time. Sort of a slow release fertilizer, but some of the nitrogen from this mulch will be release to the air as ammonia, so not all the nitrogen will stay in the manure.  This manure will slowly break down and you can mix it into the soil later to improve soil texture, microbial habitat and moisture retention. 

Step 4: Mix Manure Into Soil for Future Planting

Check out the mulch! You can see if it is broken down a bit. Mine has been decomposing...

In an uplanted plot, you can mix in the manure to let it finish decomposing there. I put about 3 inches over the bed, mix it in the top 3-4 inches of soil.

General rule is to put 1 lb of manure for every square foot of soil.  A 5 gallon bucket holds about 25 lbs of manure (depending on moisture).  I read in several places that you should not wait to incorporate the manure, as a lot of nitrogen will evaporate from manure as ammonia.

Step 5: Wait for Decomposition and Happy Soil

Now wait for the process of carbon to be tied up in reproducing microbes and then for the nitrogen to be released from dying microbes as the succession of different critters decomposes the manure mix before planting. You still might need to add some nitrogen (composted kitchen scraps or blood meal work).

How long?  This really depends on temperature, soil texture and moisture.  The more sandy and aerated the soil, and the warmer the temps, the faster the manure will decompose and be ready for planting. 

I will wait 4 weeks (watering 1-2 times per week) before planting my winter garden (kale, broccoli etc) in N. Central Florida.  If you are in a colder climate, you may not have the winter garden option and decomposition will be slow, so you should do this to your soil in the fall, and plant in the spring. 

Every state has a land grant  university with an Extension Service that publishes agricultural information including gardening, soils, composting etc.  You can search the web for information on using manure. Keep in mind that horse manure you may get from stables is different than other manures because there is typically so much bedding (carbon).  Here are a few sites with good info:
New Jersey Extension Info
Minnesota Extension Info

My home state, Missouri, publishes an amazingly good explanation of decomposition and composting. So does New Mexico!

Don't forget to water a few times a week.  Hurray for happy soil!

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    9 Discussions


    4 years ago

    Hi - I put partially composted horse stable sweepings on my flower garden spring last year and, everywhere I did, the plants are all incredibly stunted. I think there was too much urea in the sweepings. How can I rectify this?


    6 years ago on Introduction

    Thanks for yr attention to the microbiology in comparison to other poo.
    I am no expert on horsepoo, but I do remember that in my youth, farmers were all beware of horsepoo related to tetanus.



    7 years ago on Step 5

    This is a good thing to add urine too, since it is so high carbon, and pee is so high nitrogen! It has urea.


    10 years ago on Introduction

    This is a great topic for an Instructable.  I can tell you've done a lot of reading.  That's good but some of what you have read was written by scientists for scientists.  If you don't understand what they were talking about, it can get confusing quickly.  For example, microbes do not build their structures with carbon and nitrogen per se.  They eat starches and sugars (which are carbohydrates) and protein (a source of nitrogen).  They also eat vitamins, minerals, and enzymes.  I can guarantee that if you piled up some black carbon and blew nitrogen into it, there would be no living microbes in there benefiting from it. 

    25 pounds in a 5-gallon bucket is more than anyone can carry.  If I'm collecting small amounts, I line a 5-gallon bucket with a 9-gallon trash bag and fill it 1/3 of the way into the bucket.  Then I tie off that bag and reline the bucket. 

    The broadleaf herbicides to be careful of are picloram and clopyralid.  You'll have to ask the stable owner if any of his hay was tainted with those.  Usually they are used on coastal bermuda grass hay.  Then are NEVER used on alfalfa hay (they would kill the alfalfa).  Those two chemicals survive the horse digestive system and they survive the hot composting process.  They will kill any broadleaf plants with roots in your area including trees with roots spreading out long distances.  They are persistent meaning they last for years.  Ask the stable owner about the hay he uses. 

    You can tell whether composted horse manure is ready to use by the smell.  It should smell like very nice soil when it is ready.  Any composted manure that smells fresh (like a forest floor after a rainstorm) is ready to use in the garden.  Any that still smells like manure, ammonia, rotten eggs, stale milk, or is moldy smelling should be composted until it smells fresh.  For horse manure that process takes about a year.  It is very easy to tell when you have a shovel.  If it smells bad that is the smell of nutrients escaping into the air.  The ammonia smell means you are losing nitrogen.  Rotten eggs means you're losing carbohydrates.  All you have to do to save the nutrients is to cover the pile with finished compost or with dried leaves.  Those materials absorb the nutrients and prevent them from escaping.  Then the nutrients are recaptured in the decomposition process (composting). 

    Nice work on the I'ble.  Thanks! 


    10 years ago on Step 2

    me father has horse farm and local farmer uses horse manure in his vineyards. every year the farmer comes back so iam guessing it is OK.

    - careful on flowers. horse manure has too much amonia which is not good for flowers
    - horse manure that is laying for about a year it has no good properties. basically it becomes just a powder
    - in most horse manure you can find big white larvas. thay'r OK, if you plan thin 'coat' of manure because larvas will die/ eaten by birds etc.


    10 years ago on Introduction

    Hi there, my husband very kindly delivered a load of cow manure for my vege patch. My big problem is that it is still extremely raw even though it is 6 months old. If I had composting worms to it and cover with an old sheet or something will that break it down faster. The smell is terrible and he refuses to take it away again! I need a fast way to get rid of the smell and actually be able to use it. Any suggestions?


    Reply 10 years ago on Introduction

    It needs air and soil microbes to break down; spread it out and hoe it into soil is my suggestion.  


    10 years ago on Introduction

    We do this same thing, only with Lama Poo(just right for MY soil composition).
    Helps that I know a Lama/Alpaca farmer

    There is one BIG warning I'd like to add.
    If the stuff hasn't been properly composted... and I mean PROPERLY,
    Don't use it on food producing plant beds

    Besides herbicides and pesticides that dchall8 mentioned...
    There's biological baddies in that stuff.
    The heat of proper composting will normally kill any parasites and weed seeds in the poo.

    As a safety boost, When I use it on my tomatoes... I use an old microwave outside, and nuke the poo piles for a few min on high. That way I know everything but the cockroaches are dead. Can't be too safe for my tastes. Then again, tomatoes only require small batches. Larger batches of poo may also be baked in an outdoor oven, to the safety temperature(160F) or higher(like, if your oven goes from off to 200).
    "Cooking" the manure instead of composting it... still very good for soil high in clay, and low in organics. BUT, fixed nitrogen will be lower, due to ammonia evaporation during the cooking process(also smellier). So, if you're already low on nitrogen in soil chemistry, consider a few plantings of nitrogen fixers. I like a season of Soy, every 3 years. Makes for some tasty home-made tofu, or just steamed and salted edamame.