Horse Manure Compost

[PerfecTommy07]

Hi guys,

I built my first raised bed last weekend. It's 8x4 and about 14 inches deep. Now I need to fill it with some quality grow medium. I don't want to spend a ton on dept store potting mix so I have been searching the internet’s (criagslist) for cheap free organic alternatives. So far I've come across some fine folks giving away their left over soil/potting mixes but my bed is not even 1/6 full. I have a cold pile that my landscapers add to every week, and I have a worm bin that I feed weekly but none of that adds up to a full bed.
I have recently come across a great source of free horse manure that is close by. the woman has over 40 horses in her stables and says I can have as much composted or fresh manure as I can carry anytime I want it.

I am thinking I might buy some cheap top soil from HD and mix it all together with what I have including the composted manure. I'm in the dark as to what %'s I should be shooting for to achieve a good growable mix.

Can someone please suggest a winning plan of action? I'd appreciate all the details I can get as well as what to expect and pro's/con's or tips/ tricks of working manure as this will be my very first time. I have only ever gardened out of small/medium containers and always with a store bought miracle grow potting mix. This would be my first go at creating my own mix.

Thanks in advance.
PT7

[rainbowgardener]

No more than 1/3 well composted manure. NO fresh manure, unless you don't plan to plant anything there until next spring.

1/3 could be combination of the potting soil and composts you have and topsoil.

But so far (except for the potting soil) that is still a dense, moisture holding mix. So the remaining third could be any combination of perlite, vermiculite, peat moss, coconut coir, rice hulls, coarse sand, fine bark chips, etc... .something that isn't going to break down real fast, that will hold its shape and help keep your mix loose and free draining and keep it from packing down.

[PerfecTommy07]

I have tons of mulched wood chips I got dumped from a local tree nursury. they are made of various woods, cedar, brich and such. Could some of this be used as fill. they are in various states of decomp.

Can some of these wood chips be used in the mix? They will not break down too quickly.

Thanks for the reply!

[Susan W]

There are a couple of things you can get from HD for your beds. As mentioned you can use about 1/3 aged horse. Check the cheap soil. Some is great and has mixture of sand, finely ground trees and other. Some is clay and a handful will stick together. For awhile the main cheap brand we get (Evergreen) was heavy with fresh ground pine trees. A handful smells like a pine tree! The more recent shipments are better. Another bagged product from HD is Natures Helper, soil conditioner. You could go up to 1/3 of it.
You can dump all the different ingredients in, spreading out, then till or fork turn, and turn, mix.

In the spring can check, and probably add more stuff as this will have settled. Spring would be a good time for you to add a few worms, after tilling!

[toxcrusadr]

Wood chips are not a good idea when mixed into the soil. The wood requires nitrogen to decompose and may deplete soil nitrogen, robbing your plants. Used as a mulch, it has much less contact with the soil and draws N from the air instead. You can use those chips as a mulch about as thick as you want, just don't mix them in.

For most gardens a mix of compost and any kind of topsoil is fine. However my beds are raised about 3-6", I've never tried anything as deep as yours, so take that with a grain of salt. Just keep in mind that the organic portion will continue to decompose, so the bed will sink down over time. The higher the fraction of organic material, the more you'll have to make up to keep them full. That's why I go with mostly soil rather than organic matter.

[imafan26]

Instead of home depot try a trucking company that sells topsoil. If you have a truck and can pick it up it is even cheaper since the delivery charge costs more than the topsoil. Be aware though that you should check out the soil before you buy it. Often what is sold as topsoil really isn't. All it really is at best is screened soil. Topsoil is what is on the first 4 inches of the forest floor. It has a lot of critters and organic matter, subsoil, is mostly just plain dirt.

Horse manure does have a lot of weed seeds so it is best if it is composted and not fresh. Also horses are usually wormed so it may contain some drug metabolites. I don't know if that is a concern for you.

[TREGRAHOW]

Here in the UK many stables / livery yards put the horses out into fields that have been treated for weeds that can seriously harm or kill horses. Fair enough, but the weed treatment can pass through the horse and still be potent enough to kill your plantings. It can be active for up to two years. Ask at the source as to whether or not such treatments have been used, otherwise you could effectively see all your hard work come to nothing!

[imafan26]

If your beds are being prepped for spring, the easiest way to build it would be by lasagna composting. It is a long slow process, but uses materials that should be readily available to you at low or no cost. The bed started now may be ready by Spring if it is built faster rather than slower. If it isn't totally ready, you can still plant it by putting compost and topsoil on the top 4 inches and plant in that while the rest continues to cook.
Newspaper, manure, yard trimmings and grass clippings. Landscapers are usually more than happy to drop off a load if they are working nearby. Straw, kitchen waste. You may even get produce from the grocer that they were going to throw out anyway if you ask. Ask your friends and neighbors for their yard trimmings.

https://extension.oregonstate.edu/lane/s ... osting.pdf

[toxcrusadr]

Hope we can get an update on what the OP did here. Looking at the size of the bed, it would take over a cubic yard to fill it to level (maybe up to a yard and a half). I don't think I'd spend money on stuff like perlite and vermiculite for a garden bed. It's not really a container and the mix doesn't need to be that fluffy.

I wonder what is under this raised bed. Unless it is really terrible soil, 14" might be more than is really necessary to grow vegetables. Mine have done well with 6" raised beds over heavy clay. Although I can't grow carrots in that.

[ChrisC_77]

I have debated about using manure in my garden. I have a small finished compost pile with some dried leaves added later. Mostly finished though. Could I add some aged manure to the pile and let it further break down another month and then add it to the garden in February? I have read that certain crops like carrots for instance do better when not grown in nutrient rich soil as they can get leggy etc. Is aged manure a good source for root crop growing also? What defines well aged? I might have a few source and I am sure they know what is considered aged and not. I am also starting a new compost pile so I could probably add what I anticipate to be a 1/3 although this won't be used for quite sometime since I just started the pile.

[toxcrusadr]

A few manure facts:

Fresh manure should be composted - or added to the garden directly - at least 3 months prior to harvest for bacterial reasons.

"Aged" probably means they piled it up but did not necessarily manage the pile (turning, green/brown balance etc.). The center of a big manure pile may be anaerobic and still harbor e coli (etc.) even after some time.

You can tell by the appearance and odor whether manure has been well composted in aerobic conditions: if it looks like horse apples, it's not well composted. If it smells like poo rather than the pleasant earthy aroma of compost, ditto.

Should be no problem doing what you propose. If the manure is pretty well composted, it won't hurt it to add it to the pile for a couple months. If it isn't, a couple months will help it finish, especially if you can turn it once or twice.

As for whether manure is good for root crops: keep in mind that in general, compost is compost regardless of the original ingredients. In other words the process is a great equalizer. Having said that, manure compost can be higher in soluble salts (especially sodium chloride) if there was a lot of urine in the bedding, and/or it's from a feedlot where they use a lot of salt to boost weight by water retention. So it's best used in moderation unless you live in a wet climate with fast draining sandy soil. Not to deter you from manure, it's great. Note that root crops need plenty of P, which is abundant in manure. I think you'll have to grow the carrots and see how they do. :-]

I once got some manure that had been laying in a heap so long it was essentially a foot-thick layer of peat-like material that could be chopped out in blocks. I added it to the heavy clay in my brand new garden. That was great stuff!