There really isn't a consensus about plants in containers. It's all about how you intend to grow and prune the plants -- commercial tomato growers use 5 gallon pots, some use 30 gallon.

I'd say base your planting density from what's on the seed packet -- if they say to plant beans 6 inches apart, do that in the pots and fertilize appropriately.

Thanks - that is sort of the route I tend to follow, spacing around the perimeter, perhaps allowing for a couple more in the center. It is going to be interesting

SIP ( Sub-Irrigated Planters ) 25 gal Re-cycled molasses tubs, most are approx. 20" dia. x 17" tall. 8 ea. vertical sidewall holes for planting, with anywhere from 2-12 plants in the top depending on the type of plants grown.

Each tub has a 7 gal water reservoir built into the bottom. The reservoirs can be "Daisy Chained" together with 1/2" tubing and barb fittings. Use of a 5 gal bucket with a Horizontal Float Valve, the reservoirs can be kept full 24/7.