which compost

Discussion in 'Gardening & Plant Propagation' started by kathrynlmv, May 5, 2005.

  1. kathrynlmv

    kathrynlmv Well-Known Member

    Dec 22, 2004
    Hey are any of you super organic out there? What does anybody know about using compost from the city recycling plants that produce tons of compost from peoples leaves and grass clippings? What about the chemicals that some people use on their lawns? Wouldn't this be damaging to soil organisms, especially worms, which I am raising and introducing into my garden? I love the simplicity of going to a center and filling up with piles of gorgeous black stuff, but I'm concerned about the long range cost. kathrynlmv
  2. Paquebot

    Paquebot Well-Known Member

    May 9, 2002
    South Central Wisconsin
    Kathryn, on one soil forum, I'm a bit of a loose cannon at times so I may be able to calm your concern.

    Despite hundreds of "what if" scenarios, municipal compost is usually no problem. There are now very few herbicides and insecticides which last a long time. Even the nastiest stuff is now designed to quickly break down during composting. The only time you would have a problem would be if you mulched with green grass clippings which had been recently sprayed. Then the poisons would not have had time to break down into their original organic or mineral components.

    Remember this, those community compost piles are there to recycle what Nature has recycling forever. Our city has a lovely pile also. Even caught fire one time before it was properly managed! We also have community garden plots. I checked today and there were several handmade signs: "Dump Full Compost Load Here". I'll be signing up for a plot tomorrow. Hopefully mine won't be too far from one of those piles!


  3. Elizabeth

    Elizabeth Well-Known Member Supporter

    Jun 4, 2002
    West Central Minnesota
    I'll share what I gleaned from the Master Composter course I took-

    Usually herbicides/pesticides are not a problem if you are getting finished compost- as Paquebot says, the stuff breaks down pretty quickly. However, a bigger concern might be the possibility of getting diseased material which could then infect your own plantings. I agree that it seems an ideal situation to be able to get already finished compost for free/cheap, but I would err on the side of caution. On the occasions when I got material from the county I took the additional step of running it through my own enclosed compost bin before using it in my garden. My bin would heat the contents up to over 160 deg in 2-3 days. I would then empty the bin, turn the contents, put it back in the bin, and let it cook a few more days, at which point I was pretty certain that any weed/grass seeds and/or disease spores would have been eliminated.

    One of the potential problems with many municipal composting facilities is that they use a slow, or cold, composting process which does not provide enough heat to kill off the weed/grass seeds and/or disease. The material is still useful, especially if it can be gotten for free, but I would recommend a brief period of heat before using, just to be sure.