There's 173 gallons in a yard . 37 yards is 7473 gallons.

For what it's worth.... "Pine Tree Substrate"

I have to do some more reading but what caught my eye in the article.

They write, "After adding the costs of grinding and extra fertilizer, one could conceivably produce a substrate for well under $15 per cubic yard compared to more than $40 for traditional peat substrates and $20 or more for aged pine bark"

http://www.hort.vt.edu/wright/woodgro/American%20Nurseryman%20PTS%20Article.pdf

Maybe something here.... I don't even know where it can be found as yet....

I'm kind of relentless when posed with a problem... It's a curse... 

More exciting reading here. Good info...but man it's dry......

https://projects.ncsu.edu/project/woodsubstrates/documents/refereed/methods-constr-pine-tree-substrate.pdf

https://projects.ncsu.edu/project/woodsubstrates/documents/research/pine-tree-substrate-alternative.pdf

Still no idea where to get it...

Just find a source for farad #52 and buy as much as you can.
I have been using farad #52 for years and selling it to the folks who buy trees from me.
It is excellent.
I buy it by the pallet load so I can offer it to my customers at my price and there has never been a single complaint.
THEN find some bunny poop, azomite clay, lime and anything else that will supply you with miconutrients (worm castings, etc.)
It may be a tad more expensive to buy bags of soil mix but it is worth it -- in my opinion obviously.
I see people waste so much time re-inventing the wheel. I, too used to mix my own soil and try and find the perfect mix.
I think I have that in farad #52
Promix also seems to be right there as well.

That's a problem.
I'd call the company offices and see if they can help.
I did and my bags of #52 come all the way from Richmond Va at a very good price point.
Had I not been helped by the corporate offices I doubt I'd had such great access.

I use pro mix bx and bark nuggets. 50/50. I also like to water everyday and no Fafard around here.

The PITA for me this year is apparently the pine bark. I found amazing sources for peat moss, perlite and worm castings.... But I want to the store today where I used to get pine bark nuggets for $6 per 2 cubic ft. Today they said it would be $11. What the heck? Is there some sort of pine war going on? That just toasted all my savings on the other components... I'm more likely to go out and strip some trees than pay that...

There is one place that has the same size pine bark on special for $5 per bag but it's the really big chunks....up to 4". I'm not sure how good that would be for my potting mix....

So about $14 CAD :-) Ouch!

for a mill by product....

Hey joe try calling the Bradford co op I get most of my stuff from them and the prices are very good. They supply to all the nurserys and farms up here. I got a bail of Berger #6 mix which is pretty close to promix for about 16 bucks. Plus perlite in bulk for pennies compared to what hydroponic stores or nurseries are asking, for small bags.

In So.Ca. you can still get fir bark from Orchard Supply Hardware (OSH) retail @$5.00 per 2 cu.ft.

http://www.osh.com/Osh-Categories/Outdoor/Lawn-%26-Garden/Landscape-Supplies/Barks-%26-Mulches/Earthgro-2-Cubic-Foot-Bark-Nuggets/p/1857721

If you watch the sales and load up,3 bags for $10.00.

My local HD discontinued that product and now only sells the "color enhanced" garbage.

Thanks Paolo. I didn't think of the co ops...  $16....Isn't that about 500 lbs?

I've been working with a 5-2-1-1, Pine bark, perlite, peat moss, worm casting mix....    What are you using in your pots? Just the Berger #6? I've never used Berger mixes

No it's 3.8 cu feet. My mix isn't anything special just 1 part Berger #6 1 part compost I get from my parents compost bin, 1 part composted sheep manure, if I have xtra perlite I toss that in too. Composted Sheep manure at the Tsc store in town is $10 for 3 bags. I also toss a few handfuls of worm casting on top and work in. This year I got a bag of actisol 5-3-2 fertilizer going to give that a try, it's a pelletized hen manure.

Interesting that it drains well enough.... clearly it does...

I visited the bait worm farm yesterday and loaded up on those cheap 50 lb bags of castings. I met the worms face to face, as they were in the middle of changing over their containers. No bits from the bags... Very good and very cheap... Going back for a truck load when it's time to start the garden.

Thanks for the tips

I have not specifically looked for #52 but I have access to other similar mixes. However I need a lot more than a bag or even a pallet of mix. I have one supplier of mix that can deliver 2 cubic yard super sacks at $100 per yard but I need a fork lift to unload (which I don't have). A local wholesale grower gets his potting mix from North Carolina. Sometimes it has peanut shells, this time he assures me that it does not. I'll verify that and will start with 10 yards @ $100/yd. (delivered)

If that comes without the peanuts.... Yeah!

Found the small pine bark fines at local Kmart called Earth-Gro.
A 2 yard bag was $4.59.
This is the perfect size for pot mixes.
I still sometimes use the old Ray Givan recipe of 2 parts pine bark fines, 1 part composted cow manure, and 1 part perlite.

Has anyone tried Berger BM#7