For one thing, it looks it it is really really hungry. What and how often have you fed it?

Dave

Since planting out (start of June) I have only fed it once or twice. It's in a pretty fertile mix, but I guess it's consumed whatever is to consume in there by now.

I have some organic tomato feed called Bio Bact Tomato. I fed it maybe a week ago. Maybe it's time to hit it again? Should tomatos generally be fed a lot?

Plants that are grown in any kind of container will need feeding more often than plants that are grown in the ground because each time they are watered, the water run off carries away vital nutrients. Many container growers will use a dilute solution of a liquid fertilizer as often as every week depending on the condition of the plant.

Betsy

Agree. Growing in containers requires very different methods than growing in ground - regardless of the container mix used.

Plants grown in containers are routinely fed weekly depending on what fertilizer you are using. If a liquid form then diluted to 1/2 strength as Betsy said is a common practice. Some go so far as to dilute to 1/4 strength and use it every time they water.

If using a granular fertilizer (don't work as well IMO) then a fresh dose is mixed into the surface soil every 10 days to 2 weeks by many container growers.

Given the condition of your plant I would also recommend a dose or 2 of diluted Epsom Salts since it is showing signs of magnesium deficiency. Many of those fully yellowed leaves will die and fall off now as they are too far gone but some should recover some green coloring.

You can learn much more about growing in containers over on the Container gardening forum here.

Dave

Thanks! I don't have any Epsom salts, and I haven't seen them in any of my markets, but will try feeding it today.