Return to the Soil Forum | Post a Follow-Up

 o
manure, sawdust and sandy topsoil

Posted by gkb48 5 (My Page) on
Sat, Oct 13, 12 at 22:51

I am building 12 grow boxes that are 32' x 10' each out of 2x12 douglas fir (untreated). I have 150 yards of very aged cow manure and 150 yards of a sandy top soil mix. I would like to also get about 100 yards of aged saw dust to use in the mix. I'm thinking of using a ratio of 25% manure, 25% saw dust and 50% top soil. What I don't use will be stockpiled for later use or given to friends. I am planning on growing flowering perennials and I'd like to use the Mittleider method of weekly fertilization and daily root zone watering. My question is does anybody have any suggestions regarding a recommended percentage of mix of topsoil, manure and sawdust? I am in zone 5 in the northeast corner of Washington state. Any comments or suggestions would be appreciated....Gary


Follow-Up Postings:

 o
RE: manure, sawdust and sandy topsoil

A good loam soil, recognized by most gardeners as the most desireable garden soil, is made of about 45 percent sand, 25 percent clay, 25 percent silt, and 5 percent orgainc matter (manures, vegetative waste, etc.).
Your mix looks to me to have too much organic matter.


 o
RE: manure, sawdust and sandy topsoil

  • Posted by jolj 7b/8a-S.C.,USA (My Page) on
    Sun, Oct 14, 12 at 11:34

I can not see how you will manage a bed 10 feet wide.
If you are tall & have long arms maybe, but just under 6 feet tall; I have trouble with a be that is 48 inches, when it is full of plants. There weeds to pull or cover with mulch, bugs & fruit to pick, vines or limbs to tie up.
Are you putting a board down the middle to walk on?
I do not think you can have to mulch organic matter, but a mix of under 50% will give you good drainage. I have seen plants grow in rotten horse stable waste that was rotten so fine you only saw brown peat like stuff 12 to 14 inches deep. A stable had piled the waste up 10 feet high & 20 feet wide & forgot it. It rotted for a year or so & then the plant were put in, everything was so big & jungle looking.
I have a friend who is trying the no-till thing & he has a 24 inch deep bed with no soil, just organic waste. If his test plot works, I am going to try it too(will post pic's).


 o
RE: manure, sawdust and sandy topsoil

The issue with so much organic matter is that the soil volume will decrease and the soil will settle as the OM decomposes. That's not an issue with annual crops where you can easily add more OM every year, but it can be an issue with permanent crops where it's not so easy to add more material. Kimmsr's ratio is the generally accepted one for ideal soil. With that ratio your soil won't settle as much and you can add that much more OM every year as it decomposes.

And yes I'd want to rethink the width of the beds. You need to be able to reach everything in the bed without getting into it. Otherwise you're compacting your soil.


 o
RE: manure, sawdust and sandy topsoil

As far as compacting the soil goes, if the soil is highly amended, compaction isn't likely a problem. I know this from experience. I am not afraid to walk a bit on mine. Course, if the soil is highly clay, some care is advised, but I think this non walking on is perhaps overdone a bit.


 o
RE: manure, sawdust and sandy topsoil

After doing more research and hearing some feedback on this forum I'm getting the idea that there are a multitude of differing opinions about what makes good soil. Over time I'm hoping that mother nature will correct my mistakes and provide for a good growing medium. Because I have access to a lot of "green" organic material (cow manure), I am thinking of using a healthy amount of it to mix with course sand and the sandy top soil that I have. If very aged sawdust will help I'd like to add it as well. My idea is to grow flowering perennials such as shasta daisies, coneflowers, black eyed susans, coreopsis, daylillies, gaillardia, phlox, catmint, russian sage, liatris and asters as well as a few others in hopes of providing perennial color at an affordable price for those that want it. What will the sawdust add and will it be beneficial? Gary


 o
RE: manure, sawdust and sandy topsoil

After doing more research and hearing some feedback on this forum I'm getting the idea that there are a multitude of differing opinions about what makes good soil. Over time I'm hoping that mother nature will correct my mistakes and provide for a good growing medium. Because I have access to a lot of "green" organic material (cow manure), I am thinking of using a healthy amount of it to mix with course sand and the sandy top soil that I have. If very aged sawdust will help I'd like to add it as well. My idea is to grow flowering perennials such as shasta daisies, coneflowers, black eyed susans, coreopsis, daylillies, gaillardia, phlox, catmint, russian sage, liatris and asters as well as a few others in hopes of providing perennial color at an affordable price for those that want it. What will the sawdust add and will it be beneficial? Gary


 o
RE: manure, sawdust and sandy topsoil

yeah, get two gardeners together and you get three opinions, all of them guaranteed to be the only correct one. good thing plants are adaptable.

one of the better compost blends i've seen was fairly fresh manure blended fifty-fifty with fairly fresh sawdust, then allowed to sit for six months, being turned once or twice.

what's the sand for? if you have existing sandy soil, whatever you put on top will literally sink into it.

by the way...what's the point of weekly fertilizing with a high percentage of manure as a base ingredient?

if the manure is too fresh, the sawdust will act as a buffer. if the sawdust is well aged, it has no downsides and a lot of upsides. if not well aged, it may have a net effect of tying up nitrogen, but when combined with even aged manure, doubtful. bottom line, know the quality of the components, both as ingredients and as a finished mix.


 o
RE: manure, sawdust and sandy topsoil

Too much organic matter in soils can cause that soil to hold too much water and exclude the air the plant roots also need to grow limiting the plants ability to uptake necessary nutrients. Organic matter in soils is good, in proper proporations and not in excess.


 o
RE: manure, sawdust and sandy topsoil

Gardeners are like Hassidim: they agree on nothing.

my two cents: sawdust or any wood product, unless fully decomposed, is a bad mix with sandy soil.


 o
RE: manure, sawdust and sandy topsoil

Sawdust is usually considered a super brown, and I would advise against putting it directly into a soil mix. But the 'aging' process will have affected this somewhat. We just don't know how much. If you're mixing now for planting in spring, it may be just fine. If the manure is fairly fresh and high in nitrogen, it will provide some N for the sawdust to absorb as it decomposes.

I'm thinking a smaller volume of sawdust here, perhaps equal to the manure. And pile your beds high, it will sink down considerably as it compacts and decomposes.

BTW, we all know a compost pile shrinks a lot as it breaks down. So putting 50% uncomposted organic matter into a soil mix may result in only 10% organic carbon after it's aged awhile.


 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!


Return to the Soil Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.


Learn more about in-text links on this page here