@Drew: You may be wise in allowing overgrowth and then pruning back after any winterkill. In October or November I prune off up to half of all lateral growth as there is typically zero winter loss in zone 8b. @lsoh: The thickness (front to back) of the leafed and fruiting row for Logan, black diamond, and black-caps is a foot or less. Black diamond has very short fruiting spurs; the others can be a foot. I do not tip the trailers as I don't have that many trailing canes. They can be looped and threaded anywhere on the trellis. Note that my trellis requires no guying as all steel posts are connected on top with cedar in both directions, down-row and between rows. Saves space and maintaining wire tension is easy. Row spacing is 4 feet. Repeatedly bumping head on 5-foot-from-ground cedars is optional--but the pipe insulator foam does come in handy. The ground fencing: Prevents squirrel cratering

In you zone when spring garden seed come up are crack ground. Dig one roots start about foot from plant dig carefully down to root that over size pencil wooden. Cut root from plant dig outward until root get smaller than pencil cut again take out root from soil. Go back to smaller than pencil root dig about 6 more inches root bent that up toward top of soil and cover so straight up that become plant in few months a nice one. Now take piece root that came out ground and cut in 3 inch length lets just call those pieces total 4 maybe more are less. In same hour plant those root cutting 2 inches deep in soil no more no less use ruler. Don't let roots dry any when out ground water over roots just planted 30 months later you have nice fruiting plants in 18 months you have few berries. This way large plant farms do multiplication of plants so must be best way. All root cutting you plant don't take a hold and grow I think 60 will 40 want out hundred so plant accordantly. Royalty is for are on resale of patted plants over set time by paten apache and Arapaho should be out date there over 10 years old. Royalty on any plants that I bought at second year was 10 cents per plant grower paid that out my cost.

Isoh: I do think some of the roots would extend into the soil and lengthen your watering interval later in the season. But a smaller pot would probably still reduce yield and require more watering, at least in early summer. I'm getting another Black Diamond. I think I'll try both potted and in ground in the greenhouse. The plants are pretty easy to propagate so I'm not concerned about that aspect. It would also be pretty easy to repot after a few years. Good luck with your berries.

This was my second year with my TC plants growing in their new digs, like yours, in containers. I don't know what kind of plants you started with, but two of mine were rooted tips from the original plant I bought and that plant originally had only one short and narrow (less than a pencil) cane. Each plant sent up at least one thick cane during the first real growing season (I think the original mother plant maybe had two). From those three plants I harvested a gallon-sized plastic bag (freezer). Like you, I thought that was pretty good (and about the same as my boysenberries also in containers). Going into Fall I have cut off all but the four strongest new canes on each plant. Considering the vigor of both kinds of berries I think that 4 canes is about as much as you can ask from containers. Those canes have been tipped at about 5 feet and I'll let any laterals that develop grow until the dormant season and then cut them back to about a foot. My berries grow in tall cages (rectangular prisms), with one cane tied to each vertical edge. I feed weekly during the growing season with a liquid hydroponic mixture that I copied from some university site describing greenhouse production of containerized raspberries.