Chapter 2b Three Basic Gardening Systems:

The Wick Garden

The wick garden was developed to enable people to have exceptionally shallow bed gardens without the need to water several times each day. Pat Lahr, the missionary working with rooftop gardening that I mentioned in the introduction, first got me thinking about using wicks for this purpose when I visited his rooftop garden in Haiti in the late 1980’s.  

You are most likely to think of a candle or lantern when you think of a wick, where kerosene or melted wax are pulled by capillary action up the wick from the pool of liquid below. 

Water is likewise moved by capillary action if a cloth or fiber wick is placed in it. For example, if you were wear blue jeans and stand in a quiet pool of water that comes to your knees, the water wil slowly move up the leg of your pants well above the level of water in the pool.

The wick for the garden can be any kind of cloth.  For example the wick might be an old blanket, pieces cut from old clothing, a piece of carpet or a special fabric made for this purpose that is used in greenhouses to keep the soil in small pots moist until they are ready for sale.  The garden can make use of a (1) vertical wick to move water upwards as in the example above of a person standing in a pool or (2) a horizontal wick, which is a piece of cloth lying on a flat surface, to move water that is placed on one spot toward all corners of the wick. 

How thick does the wick need to be?  We have found that very thin pieces of cloth may not be able to deliver enough water to areas farther from the bucket, especially on a sunny and windy day or after the plants have developed a considerable leaf area.  Using the analogy of the wick as an irrigation pipe, a thin wick is like a small diameter irrigation pipe.  Thick wicks or large diameter irrigation pipes can deliver more water at a faster rate.  If the thickness of the wick seems to be a problem, you can try doubling it over to make it twice as thick with twice the water moving capacity or choosing a thicker piece of cloth.