Systems like the Valcent VertiCrop are the servers and mainframes of urban food production. Just as in the digital world, we also need distributed food production power brought to the people on a personal level.
Sub-irrigated (sub-aerated) planters (SIPs) like this one are the PCs and laptops of personal urban food production. You might also think of them as the iPods and iPhones of food.
There is no need to plug them into tillable earth. They are portable. All that is needed is a small space with sufficient sunlight, be it on a rooftop, balcony, driveway, paved patio or even a fire escape. They will produce more food per square foot than in-ground gardening while conserving water and valuable time. This is safe food production with no exposure to contaminated city soil.
Just as with early personal computers, you can build your own. This one is very easy to make, no power tools required. The only out-of-pocket cost was $9 for the box, purchased at local retail (a dollar store).
What we really need, however, is mass production and distribution. SIPs need to be affordable and readily available in local stores supported by visual merchandising. Obviously this would be easy to accomplish. This is very simple technology. All it will take is education and entrepreneurship in the private sector.
Personal SIPs like these would go a long way in helping us eliminate food deserts and help in the fight against obesity. Do yourself and all others a favor by trying these and then spreading the word. Just one SIP and you will be hooked!
Recycled plastics (food containers, nursery flats) create the soil platform, soil wicks and water reservoir. Five milk containers are used here (about 2 1/2 gallon reservoir capacity). Cut large slots on the bottom side of the containers to allow water entry and poke holes in the top side for aeration and drainage of any excess water. An overflow drain hole (top center) prevents over watering. Recycled water bottles create a fill tube.
Update: This overflow drain hole will work, but not very well because the soil will prevent the free flow of water. It will clog the hole. The way to do it is to connect the reservoir (in this case one of the plastic milk bottles) to the drainhole with a piece of 1/2" to 3/4" plastic tubing. This way, the water will always have a clear path to the outside of the planter. You can see that's what we did here with this sub-irrigated window box.
The reservoir inside this window box is made from inverted nursery flats. The overflow drain hole tubes on each end of the window box connect into the nursery flats on each end. Had I done this with the planter below, the tubing would penetrate the milk bottle at the top. Do this and it will prevent soil from clogging the overflow drain hole. No connection is needed between the five bottles. The large slots cut in the bottom of the bottles (not shown) allow water to flow freely between them.
Container mix (NO top soil) packed down between the recycled plastics creates the soil wicking system. The water from the reservoirs will rise by capillary action creating a uniform distribution of water throughout the SIP. Simply pour water down the fill tube until you see some water exit the overflow drain hole (top center).
The tote box lid with the center cut out makes a retainer for a sheet plastic mulch cover (not shown). Recycle the soil mix bag, black side up. This prevents weed growth and water evaporation.