The following is an excerpt from The Urban Homestead by Kelly Coyne and Erik Knutzen  (Process Media, 2010). Homesteading from their bungalow two blocks off of Sunset  Blvd. in Los Angeles, Coyne and Knutzen offer up scores of tips and  step-by-step projects for sustainable, self-reliant living in a bustling  metropolis. With more and more urbanites looking to become farmers and  gardeners, Coyne and Knutzen’s fantastic guidebook couldn’t be timelier, and the  duo’s lighthearted, thrifty approach to self-sufficiency shows there is greater  power and happiness in creating than in spending. This excerpt is from Chapter  2, “Essential Projects.”

These containers make it easy to grow vegetables in pots. They are  ideal for apartment gardening, but are so useful that everyone should consider  using them to maximize their growing space.

The problem with growing food in pots is that pots dry out quickly and it’s  all too easy to forget to water. Irregular watering causes all sorts of problems  for sensitive fruits and vegetables. Container gardening is also  water-intensive. During a heat wave it may mean visiting the plants with the  watering can two or even three times every day — obviously not a practical  scheme for someone who works away from home, or someone with any kind of life at  all.

An elegant solution exists in the form of self-watering containers. Rather  than having a hole in the bottom of the pot, a self-watering container (SWC) has  a reservoir of water at the bottom, and water leaches upward into the soil by  various mechanisms, keeping it constantly moist. The top of the pot is covered  with a layer of plastic that discourages evaporation. Depending on how deep the  water reservoir is, it’s possible to go about a week between fill-ups. This  arrangement, combined with the plastic layer, prevents both over-watering and  under-watering that can occur with conventional pots. In other words, it takes  the guesswork and anxiety out of watering.

Kelly says: I’m going to tell you right now that you can buy  yourself a self-watering container at earthbox.com. It’s great to make SWCs with found materials  and all, but if these instructions make your eyes cross, or if you just don’t  have time, there is no shame in trotting off with your credit card and ordering  a couple of these ready-made. They start at about $40.

Erik says: Au contraire, ma petite amie! All it  takes is two 5-gallon buckets, a few other easily scavenged items and about an  hour’s worth of time. Those Earthboxes are damned expensive and my time is  cheap.

A few years back, an Internet hero named Josh Mandel figured out several  different techniques for building DIY self-watering containers out of old  buckets, soda bottles, storage tubs, etc. His plans are widely disseminated  online, and you’ll find links to his instructional PDF files on our website.

Inspired by Mandel’s methods, we started making our own self-watering  containers. Each SWC is a little different, because each one, being made of  found materials, is an improvisation. We’re going to show you how to make a simple SWC out of two 5-gallon buckets. (See several of  these 5-gallon self-watering containers in use on a Chicago rooftop garden.) After you have the basic principles  down, improvising future containers on your own out of whatever you have on hand  should be easy.

The 5-gallon size described is good for one big plant. Try a basil plant in  it, especially if you like pesto. Basil thrives with the steady moisture, as  does Italian parsley, so both herbs grow huge in SWCs. Or plant a tomato, but be  sure it is a small tomato. Look for types designated “patio” or “basket” tomatoes. These are bred to perform well in tight conditions. A 5-gallon  container may seem big, but tomatoes have some of the deepest roots of all  vegetables. If you plant an ordinary tomato in a SWC, its roots may find their  way into the reservoir, and then it would become waterlogged.

For your next project, we recommend that you visit Josh Mandel’s PDFs for  instructions on how to construct a larger, slightly more complex container out  of 8- to 10-gallon storage tubs. That size SWC is good for growing a little  salad garden, a stand of greens, a patch of strawberries or even a blueberry  bush.

5-Gallon Self-Watering Container Instructions

It all starts with providing a water reservoir at the bottom of your  container. You can do this either by nesting two containers together (the top  one holds soil, the bottom one water), or by making some kind of divider that  sits toward the bottom of a single container and holds the soil above the  reservoir. However you construct it, the barrier between the soil and water  should be full of small holes for ventilation.

The water is pulled up from the reservoir and into the soil by means of  something called a wicking chamber. This can be a perforated tube, a basket, a  cup or anything full of holes that links the soil to the water. The soil in the  chamber(s) becomes saturated, and it feeds moisture to the rest of the soil.

The reservoir is refilled by means of a pipe that passes through the soil  compartment down to the very bottom of the container.

The last essential element is a hole drilled into the side of the container  at the highest point of the reservoir. This is an overflow hole that prevents  you from oversaturating your plants.