That is exactly what I did with some of my hops. I first grew them in a homemade cedar box, then the next season I dug a hole the size of the box, removed the "rootball" from the box, took some cuttings off the rhizomes, wrapped the ball with weed fabric(lay it down under landscapping to keep out weeds), then outlined the top of the soil with cedar trim. The roots go down, not out. Works like a charm.
This is one of my Chelans. Took cuttings(easy to do this way) and made some new hills with them. I wrapped this with antiweed fabric and placed in hole.
The one tall planter box has no bottom. The rest are simply outlined on top with cedar to help keep seperate on top. Am able to grow Cascades, Chelan, and Chinooks close together.
