It's going to be difficult to successfully garden within the confined space of containers using purely organic methods. Growing in the garden and growing within pots is vastly different.

The abridged version is... growing in the ground is very different than container growing because Mother Nature maintains a balance and has an army of living creatures, both small and microscopic, that continually work at decomposing, or breaking down matter into usable food for plants. This same army and balance cannot be successfully maintained within the space of containers... and very quickly, the life forms within the soil become unbalanced and can be harmful to plant health.

I suggest a more inorganic approach to growing in containers, whereby you are in control of moisture levels and nutrition, and you know your plants are getting what they require. Save the organic methods for the garden beds, where Mother Nature will help by breaking down the compost and other organic items into readily available foods for plants.

The link below will tell you what you need to know in order to successfully container garden with a wider margin for error.

Happy Growing!

Here is a link that might be useful: Container Soils - Water Movement & Retention 12

Let me add a little something to what Jodi said: I think if you follow the link and read about what makes a good container soil and what is best avoided, I think we can come down on the same page as to whether the soil is organic or not. A mix of pine bark, peat, and perlite is no less organic than a peaty soil with perlite or a compost/perlite combination.

I think where the separation in methodology comes in is in the fact that you're limiting yourself to an all-organic ideology when it comes to supplying a plant's nutritional needs, which is perfectly fine. FWIW, I voluntarily limit myself to a nearly all organic approach to supplying nutrients in my gardens and beds, using compost and regular mulch applications to improve both the soils structure/texture and nutritional content; but, I am very results oriented and not limited by any particular ideology, so I diverge from that approach when it comes to container culture and choose soluble fertilizers for containers because they are so much easier and a more effective way to manage nutrition - they work better.

Please do read the link Jodi left for you. The concept there is one that will help every container gardener that understands it. I'll save the discussion about fertilizers and only expand if your mind isn't set on using organic soil amendments as nutritional sources. In closing, I would say that definitive help can be had in putting together a nutritional supplementation program using soluble fertilizers, but the number of decisions regarding when, what, how much, how often, increase exponentially with the variables associated with an all-organic approach such that much less specific advice can be offered. No one knows how fast the organic amendments will break down, or when the nutrients will be available, or whether there will be too much or two little of any of the elements essential to normal growth - there's much more guesswork.

Al

Dear angierainbow83,

Please think about the info from Jodi and Al. I add my own story below. Since thinking through my own experiences will help me too, I hope you don't mind. I believe for me, I need to separate the garden beds from my containers; just as a two bedrooms can be used differently while still being a room, a separate approach to garden beds (to use Al's words, more "organic") vs. containers (more "inorganic") is still gardening. Good luck on your journey!

Over the past few years I seem to be suffering from a case of harvest envy. Due to space and location, I do not have the ability to grow vegetables in the ground due to shade, but I do have a very sunny spot where containers work fine. I have "successfully" grown various vegetables (and am lazily including tomatoes in this category). I say "successfully" since I have never been able to come close to the level of harvest that neighbors get when the essentially identical plants with similar methods EXCEPT the plants are grown in the ground. In fact, I can say this with with confidence since I have provided them with their plants.

I have experimented with various combinations of top soil, organic potting soil, compost and small gravel. (I won't go into nutrient supplements I have tried.) I have used about 15gal lightly-colored plastic pots raised off the ground. Given my growing climate, young plants move into these pots in early May and typically are taken down sometime after Columbus Day. The plants are still producing, but the colder temps negative influences many of the types I grow.

In the case of eggplant, tomatoes, cucumbers, and peppers, for example, my plants are 5-6ft tall and produce a crop not quite sufficient for a small family throughout much of the season. When I take the pots down at the end of the season, I typically find the exterior soil to be damp/dry while the center below the stem and near the main roots to be very wet. Further, there are many small roots near the soil surface, possible due to the thin mulch layer I applied (thinking I needed more moisture retention). There are some larger roots that spread in the pots, but not a tremendous amount. The best fruiting, distribution and size of roots was in the year where I only used organic potting soil without a mulch cover. Although I can't say with 100% certainty that by making the soil more organic I caused this problem since from year to year I changed conditions (and growing conditions change too), the evidence is pretty well stacked against me.

I'd like to ask what your growing conditions are? You are in zone 8 but it is helpful to know what climate. What sun exposure do you have? Do you water on a regular basis or need a mix to hold more moisture?

I have success growing in commercial soil, mixed with bark, perlite.

If you want to grow only organically, I would suggest you take a look at a few other forums here. This one should be helpful,

Jane

Here is a link that might be useful: Organic Gardening

While it is possible to use commercial potting mixes, be prepared to replace them at least yearly. In most cases they will break down way too fast to last more than one year. Furthermore, what defines an 'organic' potting soil? I've seen such products that are 100% peat, and needless to say, work terribly (besides for being environmentally unsound). All commercial potting mixes are 'organic' in the plain sense of the term, but specifically "organic" soils usually start with organic compost (organic starting materials and fertilizers) as a base, and go on from there to include peats, pine bark, sand, clay, sawdust, and perlite. That kind of combination would likely work wonders in the ground, but in containers there's a big chance that the compost will break down very quickly, creating anoxic conditions for the roots, which will die.

There's also the cost argument. The organic peat mix mentioned before was $28 for 2 cubic feet. If you read up on Al's mix, you can create a much better mix (gritty or not) for cheaper than that. Even if it's more expensive at the outset, it is absolutely worth every cent.

Concerning nutrients - your plant does not care whether the nutrient ions it takes up come from organic or inorganic sources. If you fear pollution from inorganic fertilizers, consider that your contribution is infinitesimally small, and that if you simply fertilizer regularly, but in tiny amounts, the plant will use nutrients as it needs, and a much smaller amount of that tiny fraction will be wasted.

I'm basically summing up what Al and other people have noted, but really do read up on the Container Gardening posts.