Thursday, April 19, 2012

Mushroom Compost

I decided to get serious about my garden dirt. 
Miss Greenish Thumb bridged my soil knowledge gap in four parts in February.  Part 4 was all about going out and getting my own compost.  I contemplated the City of Ottawa's compost from the green bin program.  Then I decided to look a bit further since you don't really know what you're getting with this kind of compost and you pay $10.50.  It's not free, so why not purchase something that's higher quality?

Then I found Continental Mushroom and I started learning about mushroom compost.  Mushrooms don't use up the nutrients in their soil so the soil is reusable.  Continental Mushroom is a massive mushroom farm that sells their spent mushroom compost.  It contains hay, corn cobs, peat moss, straw and poultry litter.  That's right, chicken poop.  Sick, I know.  And very very stinky, we discovered.

I called the farm to ask a few questions and was referred to a friendly manager.  My most important concern was whether the compost contained pesticides.  The manager said they weren't using pesticides on their mushrooms at this point in time; however, in July and August if they get a lot of "pest pressure", they may use pesticides.  Some of the compost could have been from September.  Hence, there could be traces of pesticides.  I thought about how I almost bought dump compost.  I also thought about how we eat some fruit and vegetables that are not organic; my own future kitchen compost could contain pesticides. 

My questions also led to an understanding that the compost is stored outside and could sit there for a while; hence, there's the possibility for weeds, grubs, and other pests to develop.  The spent compost is sterilized after it's used but this time outside means new pests can develop.

There's some controversy around mushroom compost, I discovered, just by a quick google search.  And I still don't quite understand pasteurization and sterilization.  But I feel good about our decision to head on out there to Continental Mushroom.   

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Bethy couldn't come with me on my Mushroom Compost Mission, so I recruited Ben and Isaac.  Family trip!  It only took us 20 minutes to get out to the farm in Metcalfe.  We brought two large garbage pails, one paper yard waste bag, a recycling bin, a little bucket, shovels, and some fliers.  I wish we had brought more yard waste bags.  We put the fliers down in the bottom of the yard waste bag.  That's a tip from Miss Greenish Thumb - prevents bag soaking and ripping.  We also needed two of us around, for sure, to lift the pails into the car.  Miss GT says that if there's only one person, you half-fill bags and pails, put them into the car, then continue filling them, using a bucket.

I forgot to put my digital card into my camera so I couldn't take any photos!  Picture a big pile of dirt and Ben digging diligently.  Then picture Isaac holding a little yellow shovel, digging beside him.  What you wouldn't be able to sense in the photos anyway is the smell!  Yuckers.  Chicken poop.  Let me tell you, "sterilized" and "pasteurized" do not mean free of fertilizer and nutrients.  The smell tells you that for sure. 

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The advertised price is $15 per cubic yard.  We were charged $10 for the compost we took.  That's the same as it would have cost us at the dump, likely, and it's better quality stuff. 

Saturday afternoon, I went and spread that compost on my vegetable garden bed and mixed it in with the dry, sandy dirt in there already.  It felt like I was adding in richness, thickness, moisture... I also put some in the little Marianna garden bed and set some aside for Bethy.  There it is: I wish this post was scratch n sniff. 

- Mary Mary

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