Hmm... I concur with farmerlon. I have serious doubts about quality of bagged compost, no matter how well it was made to begin with.
- Once bagged, the environment rapidly becomes anaerobic.
- Stacked on pallets, they would become compressed
- The standard moisture level of a compost pile seems a bit high for shipping purposes so they might dry it out a little first
- Most customers are not going to want to see bugs crawling around and out when they open the bag, so they might pasteurize the product first
That said, I like Master Nursery's Bumper Crop Soil AMENDMENT/CONDITIONER to add to my garden beds and I like Gardener's Gold Organic Potting Soil to mix with potting soil. (I've tried Bumper Crop Amendment in lieu of home-made compost and had horrible results, so I don't think it is equivalent to compost)
I've also purchased spent mushroom "compost" from Lancaster County, PA, which is not too far away from me in NJ. If you live proximate to Maine, I think Coast of Maine Lobster Compost might be a good one. I considered it, but decided the distance might be too great to count on reliable quality.
Last year, I came to the conclusion that if you have to buy them bagged, on-line or at nearby garden centers, it would be a good idea to check where they are from and choose ones that have not traveled all that far and ones that do not look like they've been sitting in the stock yard compressed and weathered (moisture as well as cooking sun) for a long time.
(Ha. I just looked up where Master Nusery might be located, and here it turns out they're "partnered" with Coast of Maine. Hmm... )
The organic potting soil when I bought them had been stored in the greenhouse or inside warehouse, out of the sun. The bag was clean and inflated (not compressed) and the contents when opened was in amazing condition -- woodsy, slightly mushroomy aroma, slightly damp and crumbly. My plants responded well.
Bumper Crop, on the other hand, are usually stacked up outside in the yard. I'm going to pay better attention to how the bags have been stored and not accept them if they're not in good condition. I know one garden center that stores one of the sizes in the warehouse. I may only go to them from now on.
Mail-order -- Certainly having them shipped direct from whoever makes and bags them would probably get you "fresher" compost than buying bagged compost that have been shipped hither and yon and stored in varying conditions between shipments.