Most of their published information about urban food production is locked in to a dirt gardening, drain hole archetype of a bygone time of rural America and WWII Victory Gardening.
The future of local food production in the city is not in the dirt no matter how much nostalgic counterculturists pine for it. Flower power had its day. Hoes, rakes, shovels and clay pots are about as modern as slide rules and tail fins.In light of this, it was refreshing to find an Extension educator with a mind of her own who has no reluctance to speak up. Unfortunately, her opinions about sub-irrigated planters (SIPs) like the EarthBox are not more widely published in the mainstream of Extension publications. To read them you would need to be a subscriber to the Chippewa Valley Agriculture Newsletter -PDF (Wisconsin).
I would encourage you to read her EarthBox endorsement that follows. It speaks the truth that you can easily prove to yourself. Just follow the directions and plant one SIP. You’ll soon know the truth. The plants and their fruits will speak to you.
The closing quote by Extension Educator Erin LaFaive "Mahlon Peterson (U of Wisconsin-Extension Agricultural Agent) loves these EarthBoxes® too. He is the one that got me addicted.
What is the best container to grow vegetables in?
In my experience, it’s the EarthBox®! EarthBox® is a brand name for a 29 inch long, 13.5 inch wide, and 11 inch high container. The success of this container comes from the special components that come with the kit and the technique in packing the soil.
The components include a screen, watering tube, plastic cover, dry fertilizer, reservoir, and overflow hole. A hard plastic “screen” is placed at the bottom of the container. It’s not a flexible mesh screen but it does have evenly spaced, small holes through it. The screen’s purpose is to hold back soil from a space of about two inches at the bottom of the container to create the water reservoir.
A tube attaches through the plastic “screen” and runs up through the soil about 4 inches above the soil. This is where water is poured to fill the reservoir. If too much water is added to the reservoir, it simply flows out of the overflow hole located on the side of the container.
Less watering is needed because the reservoir holds a supply and the plants take what they need. As the soil is depleted of moisture it will take up water from the reservoir similar to the process of a wick in a candle taking a steady supply of wax.
A black plastic cover, similar to a shower cap, covers the top of the container, just above the soil. The cover’s purpose is to help capture the sun’s rays and warm the soil and maintain a consistent temperature. A hole is poked through the cover and plants are inserted through it.
The kit comes with a packet of powdered fertilizer. The company’s study found that dry fertilizers work best with the container in comparison to water based fertilizers.
The instructions explain how to fill the container which is a
layering of soil, water, and fertilizer. The box has wheel and can be moved as the sun moves.
The instructions also explain how many seeds of each
vegetable the container can hold. Here is a list of plants that grow best in an EarthBox®: artichokes, beans, bell peppers , broccoli , brussels sprouts , cabbage, cauliflower, celery , chard , corn , cucumbers , eggplants , flowers, greens, herbs , hot peppers , kohlrabi , leeks , lettuce , melons , okra, onions, peas , spinach , squash , strawberries , and tomatoes.
Some of these plants take a good deal of space in a traditional garden; however in the EarthBox® plants have the best environment the could ask for such as no weeds and water and nutrients available at all times. The plants don’t need to extend their roots looking for resources; therefore they can grow in less space.
During the summer of 2009, I grew one tomato and green pepper plant in my EarthBox®. The tomato grew about 4 feet tall and I had to cut a foot off because my trellis was bending from the weight. The green pepper did produce a pepper or two even though it was shaded by the tomato. I had more tomatoes than I could use from that plant.
I didn’t need to water very often, perhaps two times a week during really hot and dry weather. Next summer I will need to replace the soil and dry fertilizer. The black plastic “cap” can be reused one more time. I’m adding a second EarthBox® for carrots and radishes.
Mahlon Peterson loves these EarthBoxes® too. He is the one that got me addicted.

With all due respect my dear sirs, the Master Gardener here is comparing containers not Earthbox vs. dirt. Don't get me wrong. I love my Subirrigated containers but I must humbly retort that all things being equal, my tomatoes in the groud (dirt) beat the pants out of my subirrigated container on every aspect: height, production, health, maintenance. In fact, last year when we got hit by some kind of late blight, I had less sick tomatoes on the ground than in containers. This is not to say that my container tomatoes did badly. No, they did really well and that's why I'm keeping my SIPs as a beloved and valuable way to grow plants plus in some instances, such as when we don't have the benefit of a yard, they are indispensable but I would be remissed if I did not pay Mother Nature and her 4 billion year head start on me her due respect. Plants grow on the dirt naturally, they don't crawl and construct containers to live in. I continue to read this blog daily and continue to benefit from it, I just can't put a man-made object ahead of what nature has designed.
Posted by: David in Kansas | June 03, 2010 at 05:41 PM