My birthday last month netted, among other things, about two pounds of actively bio-degrading material sent with love by my New England in-laws, who read my prior post on composting and took its message to heart. The packages contained asparagus mulch from Maine and vegetable scraps from Boston, plus billions of beneficial Northeastern microbes, as my mother-in-law Sally helpfully pointed out. In our family, the in-laws are sometimes referred to as the outlaws. Now you know why.

In any case, the birthday present I’ve really been meaning to post about is the large self-watering contained that Sally, a science teacher, sent a year ago. I’d never heard of such contraptions previously, but we found the amazing claims to be true. Last summer we grew huge quantities of Brandywine and Sun Gold tomatoes from the Box, as we called it. The Box’s trick is a nearly closed system; the bottom third of the container is a water reservoir with an overflow spigot, and the top two-thirds gets filled with soil, which sits on a screen and wicks moisture upwards. You cover the whole operation with black plastic to reduce evaporation. The plants grow deep roots, and stay toasty yet hydrated under the black plastic. (Image courtesy of Homegrown Evolution.)

Thanks to the Box, you can take a summer vacation.

This year I moved it to a sunny patio. We grew carrots this spring, mixed in some fresh compost, then put in peppers and beans for summer, which we’re growing up a trellis. The big challenge is trying to figure out how to duplicate the Box’s self-watering technique without paying the huge premium for those perfectly interlocking parts ($50 bucks retail for a 2 x 1 x 1 foot plastic container!).

The old school way is to soak pots in a shallow tub of water, so that moisture moves upwards evenly through the soil. But it’s labor intensive and lacks the efficiency of the closed system. The blog Homegrown Evolution has a terrific video showing how they put together a system from two 5-gallon buckets and a sieve. Others use retrofitted 2-liter soda bottles. And check out these Chicago rooftop gardeners’ inspiring pictures on growing an entire summer’s worth of veggies from home made self-watering containers. I’d be interested in hearing how others have adapted the technique from ordinary materials.