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The Coffee trees are planted and the capillary action in this easy to make sub-irrigated planter (SIP) is obviously working (note darker soil pattern). The internal wicking, soil platform and fill tube are all made from repurposed plastics. This is the same design as shown here and here.
Note that this planter is for interior use only. This translucent plastic box will not stand up to harsh weather and full sun. It would likely last no more than one growing season outdoors. There is also no overflow drain hole.
The only question now is whether there is enough light from the window and overhead fluorescent shop light to produce flowers and fruit.
It will be easy to monitor the soil moisture and root system development through the translucent walls of the planter box. I will also use a soil probe to directly test soil moisture. It’s as simple as that.
This same planter can be used to grow vegetables. All it needs for outdoor use is an overflow drain hole at the level of the soil platform formed by the nursery flat and juice bottle. Use the same method to sub-irrigate a sheet plastic lined raised bed.
This is the simplest method of making a SIP that I know of on the web. All you need is a hot tool to poke holes in the juice bottle and nursery flat and a hot knife to cut a slot in the bottom side of the bottle(s) to allow free flow of water.
There is no need for power tools, PVC tubing and complicated fabrication. This design will work for any watertight container. It is a truly universal method for creating highly productive and water conserving SIPs. You can grow fresh food on any paved surface, balcony or rooftop in the heart of the city. All you need is enough sunlight. There is no need for finding scarce tillable land that may well be contaminated in urban locations.