When is a tomato (or pepper) root-bound?

[fireman949]

This is my first year really getting good plants from seed. Previous years haven't been as profitable, but I've a better growing frame / light setup and I started mid-January for my Zone 7A.

Because of what I think is a good start, I've potted up my peppers once and tomatoes twice. Below are some pictures of my root balls on peppers and tomatoes - I'm curious if these are considered lightly root bound, medium root bound, heavy root bound, or not at all (or is there a light/medium/heavy)?


First - tomatoes :

These were seeded on or around 1/15 and potted up to 4" round pots from Lowes around 2/05. Fed with light fish emulsion and the plants themselves were about 10" - 12" tall and fairly stocky.




I potted most of them up to round pots 4.5" wide and tall to give away later, the rest I planted.



And the peppers :

These were started the same time as the tomatoes and potted up at the same time to 3" square pots. The pepper in the picture is 8" tall from dirt to tip and is the tallest of the bunch.




Because I think the peppers are close to root bound and I don't have 32+ larger pots to pot-up, I'm going to start hardening off and get them in the garden this week. The forecast for the next 15 days has highs in the mid to upper 60s and lows in the mid 40s with a few nights at 38. I have raised beds with a visqueen cover I can put on if we expect anything below 40.

To me, something like this is root bound:



but I think mine are just at the - need to be potted up stage?

I'd just like to know what is considered root bound. I know at this point with both peppers and tomatoes I need/needed to do something.


This pepper is ~6" tall which is more like the rest of the peppers: