Hmm, very good points. The only thing is, much of the compost that nurseries sell originated at municipal dumps! The bagged stuff is SUPPOSED to be heated enough to kill pathogens, but, who knows.

I like to know the pedigree of my compost. If I don't know that it ever got hot enough to kill the pathogens, I shy away from it.

Municipal composting operations tend to be a lot more efficient at the composting process than do many home composters, primarily due to the scale of the operation. And many - but not all - must adhere to some rather stringent regulations as well as far as temperatures maintained and the duration.

A hot composting process is very good at eliminating the majority of plant disease pathogens. And larger scale (bigger than a backyard compost pile) municipal compost operations are very easy to achieve sufficiently high temperatures to kill off pathogens, both plant and human. Locally, there is little, if any, evidence that municipal compost contributes to the spread of any plant diseases. None that I have ever encountered and I've been working with and using the stuff for many years. It is a lot harder to eliminate many persistent weed seeds than it is most pathogens.

Here is a link that might be useful: article on plant pathogens and composting

Good to know. Thanks Gardengal, good info, eases my mind a bit.

So, from a standpoint of quality, does it matter if I get compost from the city dump, or if I purchase composted manure from my local box store? Is there a preference, or is it a matter of personal choice?

I am of the opinion that more we recycle locally, the better. And, if the city sees a demand for the compost product, the more inclined they are to continue the program. As for quality, its a crap-shoot unless you check it out. Some compost from some cities is terrible, as is some store bought stuff, so I make my own.

tj

If I had my druthers, I'd prefer compost made without wood products, paper/cardboard products or bio-solids. Sawdust, paper, ground up pallets etc, probably doesn't have the micro-nutrients a good leaf compost would have.

Like GG48 said, most large composting firms would have guidelines as to pathogen suppression so I'd not be too concerned about that but it might be nice to know the original feedstock.

Lloyd

I have seen the five area community free compost and leaf mold piles. Of the two the safer is the leaf piles. All sorts of garden waste goes into the ground wood. That includes anything a community member hauls in and tosses on the pile.

In all five of these operations not a single one has a good control. They joined hands to buy the huge grinder. No one does anymore than grind it twice and pile it up . That is called free wood chip mulching compost. It all or nearly all gets picked up and used as mulch.

After getting a load with thistle that I've been fighting for years I prefer going to the tree trimmers and purchase their twice ground. One load of five cubic yards at twenty four dollars a yard delivered is my cost for the clean product.

Mulch from the city is another matter and can be very suspect. I've seen all sorts of things in that in various communities. But compost, around here at least, can be very good or, well, not so good.

tj

I agree on the municipal mulch, hate to say it, but we've used tons over the years and we do have every weed under the sun, not to mention diseases.

As far as compost, gardengal is right, these big operations have big piles that should heat up well. If you want to know anything about the quality of your local product, there will be a person in charge of that operation you can talk to about temperature, ingredients, how long it ages, whether they do any testing for nutrients or contaminants, etc. Just call the solid waste people.

Sorry to bump an old thread, but dump compost came up in a conversation I had recently. I was talking to the owner of a local nursery/supply store and asked him about dump compost, he said he wouldn't use it. He didn't mention anything about weeds, but said you have no idea what kind of chemicals might be in it; lawn, pesticides, etc.
Made a lot of sense to me.

g'day oldpaddy,

maybe he could have ellaborated more, they bring the composed waste from the sewerage farms and mix that in nowadays low grade industrial waste and hospital waste goes down the sewerage.

with the look behind the picture policy, saw a tv stint for promotion of the stuff a night time stint, in the background an industrial liquid waste truck emptying his load into the material as they mixed it in. the reporter did ask about monitoring txic levels the answer "oh the epa look after that, but we pass their test".

yep users have no idea what the bencmark is or how often it is modified upward?

as far as i am aware this product is the base for all or most potting mixes, so very hard for gardeners to get around it.

use it with knowledge and caution maybe?

len

Here is a link that might be useful: lens garden page

Well... Luckily I live in an area where we don't have to worry about that. Only a few towns have a sewer system where I live, very little business outside of the service industry and the closest hospital is 45 miles away. He was talking about what chemicals people use on thier lawns and flowers.
That's amazing that that's what they do in some areas.

Well, I love the compost from the dump. LOVE it, depend on it totally. My whole "barrow" gardening system is based on it, and I feel like I've finally learned how to garden because of this great black sterile stuff!

Our dump is run very efficiently (too much: signs everywhere, do this, don't do that) and they are out there constantly bulldozing the great long heaps of wood mulch and compost. It gets so hot NOTHING is left alive, and that's the secret for me: every garden I have gets a generous topping of this stuff and that suppresses weeds. Finally, finally.

And of course it's fertile and made of organic materials and also friable: we grow HUGE potatoes in this stuff combined with our own (not sterile) compost and a fabulous amount of manures. (We keep chickens, horses, and sheep, among others.) See below.

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Dump compost only costs $10 the truckload, aned they load with a big scoop, and early last spring we were getting some and a local nursery guy was there with a big dump truck getting filled up and just beaming ear-to-ear he was so happy to be getting started with gardening season!

It is so popular with landscapers and nursery people that they ran right out in June; I went up there and came back empty! Now I know and make sure to get my supply topped up in off months.

I also use the "black compost" (which is what I call it to differentiate it from our own huge amount of compost which is brown and has weed seeds) to mix with peat moss and Pro-mix and builders sand for my greenhouse potting mix and for seed flats.

Great stuff, no problems at all.