It is the school project. They had no budget and no soil...only dirt sooooooo. I cut about a 9" square out of the bottom of the box then lasagna'd the box using free Starbucks grounds and kitchen scraps for the nitrogen and shredded newspaper and brown grocery bags for the carbon. I added a little homebrewed microbes to get the process started. The boxes are topped off with about 4" of potting mix. Everything is short rooted and fast growing because I have 7th and 8th graders who have the attention span of a gnat on some days. And, we needed something to offer instant gratification while we hole compost the ground for future planting. We have carrots, lettuce, onions, bok choy, radishes, spinach and peas. I am going to put tomatoes in boxes...got the idea from you really. You sent me something about growing toms in compost so I am going to hole compost then place the box, put in more compost, add some soil, then mulch. Right now we have ripe tomatoes in ebuckets. BTW the boxes held up real well in the recent rain. We just had a visit from three other schools who want to garden but have no budget either and they could not believe we were gardening in cardboard boxes so they had to see for themselves. We may have more Redneck Cardboard Box Gardens around our town.