Gardening is thirsty work, and a little bit of work with an empty pop bottle can slake your thirsty garden.
I found this website at the tail end of my 2008 gardening experiment, and implemented it with a couple of plants to great success. Last year, I scrounged as many empty bottles as I could and finished with seven plants happily dipping their toes. This year, a soda-water-loving pal has been stockpiling his empties, and the promise of an almost fully self-watering container garden is upon me.
Some people argue that the end result is not very pretty, but to my eyes, the exposed earth is far more appealing than the branded plastic pots I’ve salvaged from the local garden centres. I would also argue that, once the plants get established, you’ll be so overrun with healthy foliage that the pots themselves will hardly be noticeable. Plus, you get the advantage of being able to see which plants need a top-up, and just being able to watch the development of the root system is worth the price of admission. My ground cherry from last year failed to fruit, but it wasn’t for lack of trying: The root ball spilled out from the neck of the bottle and took up nearly half of the reservoir.
The instructions given on the site offer good basics, but for anyone wishing to try it, I’d advise tweaking a few steps: First, the “poke holes through with hot nails” is both unacceptably dangerous and time-consuming. I successfully used an old, blunt Exacto knife, pushed from inside the cut bottle (so there’s no “wall” created to block drainage) just enough to create a hole, then twisted to enlarge it. Occasionally the knife would cut a slit in the plastic, but I didn’t observe this to be much of a deterrent to the plants. I also skipped the pierced-cap and string “vein” proposed on many other bottle-planter sites, and instead stuffed the necks with cotton batting. Lacking small rocks for drainage, I layered dried grape stems to good effect. For nitrogen-loving plants like my tomatoes, I threw a handful of seaweed in once I’d covered the cotton batting with a couple of inches of soil, then topped the rest off with potting mix and some worm castings.
You’ll need to top-water until the roots start to creep towards the neck, but once the plants are established, this is a very easy garden to maintain. Just insure that the reservoir is topped up every day, and the plants will thrive. I had excellent success last year with my tomatoes, parsley, basil, and even the taprooted avocado I coaxed to sprout in my worm bin. This year, I’m adding snap peas to the pots as well.