I've been playing around by filling a few containers with the leaf litter, sand, and freshwater aquatic plant residue that washes up on a neighbor's beach on the shore of the local lake. He has been bringing it to me to dispose of, he gets several hundred lawn and leaf bags full each year. It is mainly oak leaves by the time he rakes it from the water's edge. At least, oak is the only discernible leaf left with any size to it. Many other tree species line the shores of this lake, which has homes all around it, a lot of willows and maples as well as oak. I suspect those leaves just break down sooner into small particles too fine to identify.

So far, it seems to be making a good, and free, container mix. The sand keeps it well aerated, the oak leaf residue seems to retain sufficient water. I haven't checked the pH, but I'm not too concerned, since my water is naturally alkaline, it will eventually come up if it's too low. I've planted a large tub of melons, a couple of tomatoes, some various annual flowers, a couple of dwarf butterfly bushes, and some conifers and deciduous trees, and so far so good. I am, however, fertilizing with Osmocote and a liquid all purpose 20-20-20.

With that rich a mix, I bet if you just fertilized a tub right after you woke up maybe once a week or two, it would do even better than the Osmocote or 20-20-20 :)

Nice series of posts. I am also interested in zero cost container gardening and I am also starting to conduct experiments. For the sticklers out there, I am not counting the containers, my time, acquiring a base of seeds and tools, etc. when I refer to zero cost. I am referring to seed, water, soil, and nutrients.

By using heirloom seeds and letting some plants go to seed every cycle as well as by trading seeds with others I believe I have the seed part covered. By installing a good rain barrel system I pretty have water covered so long as Mother Nature cooperates; if not then city water can supplement. But what about soil and nutrients?

I tried composting but compost gets too compacted in containers just as the big box store soil mixtures do. Leaves, stumps, sticks, etc. seem like they could help. I will be reading your posts for more ideas.

I recently started experimenting with the pine bark fine based soil recipe posted by Al ("Tapla")... but it's certainly not free; I'm thinking it's about $5.00 per cu ft not counting time, labor, and gasoline. Will my yields make up for this cost? I don't know yet. This mix also requires supplemental nutrients to work so I also added Dynagrow Foliage-Pro 9-3-6 which cost me $23.99 total for a 32 ounce jug at Amazon.com. 32 oz = 192 tsp so each tsp costs about $0.13. Assuming that I add 1 tsp per plant per week and an average plant life of 4 months we're in the $2.00 to $3.00 range for cost per plant.

I couldn't find the pine bark fines nearby but Wal-mart had a close match: American Countryside soil conditioner from Sims Bark Company out of Muscle Shoals, Alabama. After sifting out the very small particles (which makes up about 50% of the volume) its remaining pieces are mostly under 3/8" and are made mostly of pine bark so no there is no need to sift a second time to get rid of any larger parts. The perlite and sphagnum peat are easy enough to find but not cheap.

Anyhow thanks for your posts. If I come up with anything noteworthy in my own experiements I will be sure to share.

I'm surprised planting in uncomposted oak leaves isn't causing showing any issues.. the tannins are supposed to be quite problematic. I use freshly fallen live oak leaves as mulch, but I have somewhat alkaline clay soil underneath to bind and neutralize the acids.

Perhaps just another example of laboratory results not bearing out in the field.

I do a similar approach in the field. I get all my inputs from my own property much of which consists of compost made from mostly grass clippings and oak leaves. It is very productive.

That being said, I have tried to do organic methods in containers and have found it very problematic in many ways, and now do containers in 5-1-1 with great success, which is still much cheaper then using commercial potting mixes.

That being said, I wish you luck in your experiment as I realize how difficult organic is in containers where the environment is too small to maintain a full ecosystem.