Tim Anderson is taking on an ambitious project he’s calling the “nomadic orchard:”

A portable life support system for fruit trees. Giant self-watering planters. The trees can be moved anywhere with a forklift or a truck. A 70 gallon water tank under the tree wicks moisture up to the tree’s roots as needed. Rain water and sunshine are free. Fruit trees are free. Dirt and boxes are free. You do the math. The big plastic tubs used here are “macro bins” the winemakers next door gave me. They are about four feet square. Seen here with a fig tree and a fruiting cherry.

There’s an interesting discussion in the comments about plant roots.