San Francisco, however, has a unique form of precipitation that is widely known but rarely recognized - fog. San Francisco averages 108 foggy days every year, on average, or almost a third of the year. This fog usually is deposited in such a thin layer on the soil that it quickly evaporates after sunrise. However, a new device is changing that.
|The great Golden Gate Bridge enveloped in fog, an important source of precipitation in coastal California (Photo from NPS, public domain)|
A device called the Groasis Waterboxx Plantcocoon®, or Waterboxx for short, is able to collect and store this fog. The Waterboxx was designed to grow trees in deserts or in areas bordering deserts, and to accomplish this goal it takes advantage of many techniques first developed by nature. One of these techniques is the Lotus Effect. The lotus leaf, in nature, exhibits a property called superhydrophobicity, roughly translated as extreme resistance to water sticking. The lotus leaf has this property because of tiny pyramids on its surface that prevent water molecules from attaching to each other. The lotus leaf does this to keep dirt, bacteria, and fungi from sticking to its leaves. You can see this illustrated below.
|Graphic by William Thielicke showing pyramidal structure of the surface of the Lotus leaf. This surface guarantees that water won't stick to the surface of the lotus leaf, or the Groasis Waterboxx lid that has similar microscopic pyramids on its surface.|
|Water sticks to most surfaces, but not the lotus leaf - From Ralf Pfeifer via Wikipedia |
The Waterboxx was designed to plant trees in the desert, and as designed can provide all the water a tree needs for over a year with no human intervention (watering) after set up. It allows you to plant bare root trees (available here), in the Spring, Summer, Fall and the San Francisco area Winter. These trees won't need any watering or work until they have almost outgrown the Waterboxx, at which point you lift the Waterboxx up and reuse it for up to ten years.
The Waterboxx isn't just used to grow trees, but also can be used for any garden plant with a compact central stalk, like tomatoes, peppers, melons, and zucchini. You can buy the Waterboxx or see it used to grow many plants on the Dew Harvest website here.