I use a mix of about one third to one half municipal compost to the remainder Pro-Mix BX, plus some time release fertilizer. You could add some lime too, but the municipal compost around here has a good amount of both calcium and magnesium. I think an 18-20 gallon toteful is about $1.25, a scoop dumped into the back of your pickup truck is $13.00. Pro-Mix BX w/mycco is around $18 for a 3.8 compressed bale, which expands to about 7.5 cu ft, or about 60 1-gallon pots. Hope this helps. Mark

This is a copy/paste job from something I left on another thread a while ago: In my estimation, the only convincing case to be made for reusing container soils is one of economics, and you'll never find me argue against making that decision. If you can't afford, you can't afford it. That said and setting economics aside, you might decide to reuse soil for reasons other than economical. Perhaps the effort involved with acquiring (or making your own) soil is something you might not wish to go through or be bothered with. In any case, it would be difficult to show that soils in a more advanced state of structural collapse can somehow be preferred to a soil that can be counted on to maintain its structure for the entire growth cycle. So, if the economic aspect is set aside, at some point you must decide that "my used soil is good enough" and that you're willing to accept whatever the results of that decision are. All soils are not created equal. The soils I grow in are usually pine bark based & collapse structurally at a much slower rate that peat based soils, yet I usually choose to turn them into the garden or give them over to a compost pile where they serve a better purpose than as a container soil after a year of service. Some plantings (like woody materials and some perennials) do pretty well the second year in the same bark-based soil, and with careful watering, I'm usually able to get them through a third year w/o root issues. Watering habits are an extremely important part of container gardening. Well structured soils that drain well are much more forgiving and certainly favor success on the part of the more inexperienced gardeners. As soils age, water retention increases and growing becomes increasingly difficult. If your (any one's) excellence in watering skills allows you to grow in an aging medium, or if your decision that "good enough" is good enough for you, then it's (your decision) is good enough for me, too. The phrases "it works for me" or "I've done it this way for years w/o problems" is often offered up as good reason to continue the status quo, but there's not much substance there. I'm being called away now, but I'll leave with something I offered in reply on a recent thread: "... First, plants really aren't particular about what soil is made of. As long as you're willing to stand over your plant & water every 10 minutes, you can grow most plants perfectly well in a bucket of marbles. Mix a little of the proper fertilizers in the water & you're good to go. The plant has all it needs - water, nutrients, air in the root zone, and something to hold it in place. So, if we can grow in marbles, how can a soil fail? Our growing skills fail us more often than our soils fail. We often lack the experience or knowledge to recognize the shortcomings of our soils and to adjust for them. The lower our experience/knowledge levels are, the more nearly perfect should be the soils we grow in, but this is a catch 22 situation because hidden in the inexperience is the inability to even recognize differences between good and bad soil(s). Container soils fail when their structure fails. When we select soils with components that break down quickly or that are so small they find their way into and clog macro-pores, we begin our growing attempts under a handicap. I see anecdotes about reusing soils, even recommendations to do it all over these forums. I don't argue with the practice, but I (very) rarely do it, even when growing flowery annuals, meant only for a single season. Soils don't break down at an even rate. If you assign a soil a life of two years and imagine that the soil goes from perfect to unusable in that time, it's likely it would be fine for the first year, lose about 25% of its suitability in the first half of the second year, and lose the other 75% in the last half of the second year. This is an approximation & is only meant to illustrate the exponential rate at which soils collapse. Soils that are suitable for only a growing season show a similar rate of decline, but at an accelerated rate. When a used soil is mixed with fresh soil after a growing season, the old soil particles are in or about to begin a period of accelerated decay. I choose to turn them into the garden or they find their way to a compost pile. Unless the reasons are economical, I find it difficult to imagine why anyone would add garden soils to container soils. It destroys aeration and usually causes soils to retain too much water for too long. Sand (unless approaching the size of BB's), has the same effect. I don't use compost in soils because of the negative effect on aeration/drainage. The small amount of micro-nutrients provided by compost can be more efficiently added, organically or inorganically, via other vehicles. To boil this all down, a container medium fails when the inverse relationship between aeration/drainage goes awry. When aeration is reduced, soggy soil is the result, and trouble is in the making. Al

I have two bins worth to worry about. I will either add them to my beds, store it for use for later or simply add it to my compost bins. Expensive compost but it's already paid for. As for your small potatoes, I haven't harvested yet so I can't say, but if bushiness is any indication, I've got a lot growing. Try straw if you want a lighter fill material. /shrug Here is a link that might be useful: Sinfonian's garden adventure

actually, come to think of it, i used about %20 local soil on that jabo the rest were bark fines and compost. most people suggest not using local soil becuase of weed seeds etc... i never have a problem with it. it always seems a great addition. i leave 1/2 inch on the top of my containers for mulch... no weeds and it keeps the soil cool. i bought it as a 3gal, and within 16 months had a dozen fruit the Jabo is in the middle of the pic. in a 7gal container. fruit and flowers. (small white bumps are flower buds). you can even see the tips of the leaves are burned when it didnt rain, and i forget to water it for a week.