Reaping a dual harvest: tomatoes and potting soil
For many years now I have grown tomatoes by the ``on-going compost'' method that is said to have originated with the Chinese. After the initial setup, this method requires little effort to maintain and while it's producing tomatoes it's making black, rich, crumbly compost for next year's garden or potting soil. It works this way:
1. Take a piece of chicken wire eight to 10 feet long and 30 or so inches high and form it into a ring.
2. Fill the ring or cage almost to the top with a mix of grass, hay, leaves, and any kitchen waste you might have on hand along with a couple of shovelsful of manure and/or finished compost. Thoroughly soak the mix. Adding some biological compost starter would help but is not vital. Lacking manure, you might sprinkle some soil and nitrogen-rich fertilizer, natural rather than chemical, into the mix. Don't use lawn-fertilizer unless you are absolutely sure it contains no weed killers.
You can start this as early in the spring as is feasible so that the composting action is well underway by the time tomato-planting season rolls around. On the other hand, the system still works well even if you set it up immediately before planting.
3. From now on, add table and kitchen scraps to the cage as they become available, covering them with more hay etc. or soil, or you might simply bury the scraps in the mix. My preference has been to leave the kitchen scraps exposed for a day to let the birds enjoy themselves for a while. Don't add meat scraps which will attract unwanted animals to the cage.
Have no fear that you will ever overfill the cage, for the ongoing composting action will steadily reduce the bulk of the organic material.
4. At the appropriate time, plant the tomatoes around the outside of the cage. Better still, form a narrow raised bed (at least 12 inches wide and up to 12 inches deep) all around the cage and plant the tomatoes in that. I used this latter raised-bed approach in newly started beds for the first time last year and the plants grew much more vigorously than in a nearby flat-bed planting. This may have been due to the more rapid warming of the soil in the raised bed but also, I believe, because the roots could easily grow sideways into the steadily forming compost.
5. Use stakes or wrap a taller piece of fencing most of the way around the cage to support tall-growing tomatoes. If you use tall fencing, remember to leave an opening at the back so that you can easily add kitchen scraps to the pile and reach in to pick ripening tomatoes.
6. Water the tomatoes once a week in dry weather by thoroughly soaking the compost.
All season long tomatoes grown by this method send probing roots under and into the compost to feed on the nutrients being released by the decaying organic matter.