Right now for my own mix I'm using a bag of composted cow manure (1 cu. ft.) plus 5-6 1 gallon pot fulls of sphagnum peat moss to bulk it up and add the "fluff factor" and roughly 2 qts Perlite. So far this is the best consistency I've come up with for my own stuff. I'm not sure what it comes out to per cubic foot but for roughly $3.50 per batch I can pot up 16 1 gallon plants so that's less than $0.22 per pot.

For my smaller veggies that I start from seed as well as strawberry daughter plants and small daylily divisions I pot them up into either 8.5 oz or 20 oz styrofoam cups and I can get somewhere in the neighborhood of 175 of the small size potted and about half that of the larger size potted in one batch. So that's under a nickel per pot using the cups.

I had been using a cheap brand of composted Cow Manure from Lowes that I actually liked (as far as color/texture, etc..) that cost about $1.50 per bag. They were out the other day so I got some at Walmart instead. BIG mistake. I opened it up and it was half clay, no wonder it was so heavy. I dumped it out in my garden and I'm taking the unopened bags back for a refund....it was horrible. And it was $1 more expensive than what I normally use. If I wanted clay I coulda' just dug it out of my yard!

The best source for info on container mix recipes is the Container Gardening forum here as that is their focus - as opposed to folks who do in-ground gardening.

That said, there are literally hundreds of discussions all over the forums here on 'best container mix', 'best potting mix', 'make your own recipes' for container mixes, etc. that the search will pull up for you.

Many of them address specific plant's needs as no one mix works for all. Many cover the pH issues, water retention/drainage issues, compaction issues, nutrient supply/retention issues, mix sustainability issues (use and reuse), etc. so lots of good information is already available.

Common points reconfirmed by all the discussions is that (1) container gardening is unique, a different world that shares little in common with in-ground gardening, 2) that the use of "dirt"/garden soil in a container is not recommended for several reasons, that (3) there is a big difference between "potting mixes" and "potting soils", and that (4) there are many high quality bagged potting mixes available depending on local availability.

Probably the one container mix that gets the most discussion on the various forums is the 5-1-1- mix recipe discussed in great detail over on the Container gardening forum.

Dave

Here is a link that might be useful: Container Gardening forum

squirrellypete,

Your mix sounds like mine but with perlite. I dont use perlite due to cost.

digdirt,

The 5-1-1 costs me like 6 bucks a cuft to make. Being I get 5 gal of pine fines from a 2 cuft bag of bark that costs 4 bucks.

This post was edited by TheMasterGardener1 on Sun, Feb 10, 13 at 14:49

The 5-1-1 costs me like 6 bucks a cuft to make. Being I get 5 gal of pine fines from a 2 cuft bag of bark that costs 4 bucks.

I'm not saying you have to use it or even recommending it necessarily. I'm just pointing out that the recipe is readily available and well proven for containers. And you also have to factor in its multiple-year use when compared to other mixes. So while it, or any other mix for that matter, may be more expensive up front it's life span has a $ value too that can't be ignored.

Personally I don't use much of it. I do lots of large (15-20 gal) container gardening in addition to in-ground beds and i use ProMix BX almost exclusively. Given its bulk pricing when purchased in large bales and its multi-year life expectancy and its ready tolerance for amendments I think it is hard to beat.

At some point though, if you are going to container garden, you have to accept the built-in limitations of it. The law of diminishing returns kicks in if cheap mix is the primary goal rather than the usual goal of max production out of limited space.

There is a break even point where cost of the container mix balances with good levels of production. But the cheapest end of the scale ain't it. :)

Dave

The 5-1-1 costs me $2.67 per cf or less than 36 cents a gallon. In contrast, Miracle Gro potting mix is sbout $1.35 per gallon. Home Depot sells 3.8 cf of peat for $11 or about 40 cents a gallon. I can buy pine bark fines from several sources for about 23 cents a gallon. So I don't understand how you can say a mix that's 90% peat would be cheaper than one that is 70% pine bark. The most expensive part of 5-1-1 is the perlite, which is usually more that $1 a gallon.

Those bales of peat expand to twice the cuft listed on the package. So the 3 cuft bal I get is 9 bucks and it expands to 6 cuft. So thats 1.50 a cuft. I wish I could could get pine fines that cheap. I have looked and the best I can find is bark that I have to sift and end up getting 5 gal of pine fines for 4 bucks or so. I do use the 511 for some house plants and have at least a good 1.5 cuft I can use this season. i am thinking about getting more containers so a cheap potting soil is really needed.

I do understand that a mix with high porosity will yield more per square foot like some were saying. I may want to consider that. I do need the container to hold a lot of water as I do tend to grow large plants in small containers.