How are your tomatoes doing?

You said you "water regularly."
What does that mean? How do you decide they need water?
Then how do you've added enough?

When seedlings, I water every day, but when out in pots (I have many pots full of all sorts of plants) they get watered en masse "when they look like they need it"!!! For 20 mins approx. I don't have the time to test each individual pot I'm afraid

As a follow-up, it turns out I have tomato wilt, caused by a soil borne fungus. Sadly I have had to pull all my tomato plants out and discard them and the soil, clean everything in bleach, and invest in new potting mix.
Advice to all - if you have a problem, consult an expert!!!!

So you say you have wilt caused by a soil fungus, how was this diagnosed? I am having similar problems with my tomatoes at the moment. I have them in brand new pots with brand new good quality potting mix. Who is the expert you consulted that I may also be able to have them advise me?
cheers John

I've had a similar issue for years (fusarium wilt) and this year have started grafting my heirloom seedlings onto Maxifort and Collosus rootstock. I have a friend who only uses grafted tomato plants and is quite successful. I'm counting on the same success! I wish you well. If you are planting heirlooms, you may want to look into grafting.