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colorado

How much OM is too much, I am thinking about bringing one to over 90%, is this too much?????

8/19/2003 8:47:27 PM

Montoursville, PA

Whew! I would think the absence of mineral ballance would be significant if that level of humus or organic materials in process were achieved. I never heard that question ask that way before. Don't really know.

Can only think of one or two similar plant environments That would be mushroom compost and the piles of municiple sludge I have seen. Neither by themselves proved to be good growing mediums.

I've always strived for 10%. I may have had that much in a given year or two. I'm pretty sure I never could exceed that level by much. This would be one heck of a good growing medium.

8/19/2003 10:50:14 PM

Utah

along the lines of what Doc said. you need more than just OM to have good soil. OM is a great soil condisioner. It is a long term- slow release fertilizer. it also helps hold water in the soil. I think 20-30% would be the high end for us AG growers.
it also depends on how composted it is... if you have 100% OM non- composted patch 2 ft deep ... then all you have is a compost pile. not a good thing to grow in... ask Brett Hester... :)

the other thing you have to remember is that OM is measured in % by weight not volume. if you take 1 cubic yard of "top soil" and add 1 cu yard of OM you won't have 50% OM, depending on soil type and OM type, I think you'd be lucky to end up with 15-25%.

8/20/2003 12:10:15 AM

[email protected]

Steve,
Your CEC would end up very low. You can do this, but a custom fertility program would be needed. Ask Chuck (alexsdad) about this. He's growing in straight leaf compost this year.

Steve

8/20/2003 12:54:21 AM

Caceres, mid west of Spain

You don't need so much OM, neither your plants. Great soils you can find with OM% from 5% to 20%. Balance and health is much more important.

Carlos

8/20/2003 1:48:50 AM

Garden State Pumpkins

I'm growing in straight leaf compost out of necessity not by choice. My situation called for massive inclusion of fill to level out a slope and condition a clay/rock hard pan. Places in the landfill are six feet thick of leaves. So maybe the top 12 inches have been rototilled into black humus. It still is not good growing medium. Weeds that are thick in the hardpan are very sparse in the leaf compost if any at all. Areas where I have crushed the clay and put back into the leaves are showing much better growth and where the hardpan meets the compost and is mixed is probably my best growing areas. I didn't do a soil analysis this year but will at year end I really didn't expect it to grow anything...If I didnt Plant in there I doubt even the crabgrass would take hold...I suspect it will be another 2 years before I get it right. Where the mineral content of the clay is restored to the top soil.

8/20/2003 6:34:03 AM

Syracuse, NY

just plant some of those really nice Gerry seeds i sent you....they'll grow in anything! lol 'pal

8/20/2003 1:47:25 PM