It's all got to do with the potassium or boron levels - you will find this article interesting. Also google results for blotchy tomato ripening.

http://agdev.anr.udel.edu/weeklycropupdate/?p=1503

http://agdev.anr.udel.edu/weeklycropupdate/?p=1463

Interesting articles, Pudge.
I've noticed the yellow shoulder in some varieties in my garden. I've never had such disappointing results in growing tomatoes as the last couple of years. I'm ready to give up on them.

I feed my tomatoes Miracle Grow Ultra 15-30-15 (the yellow bucket) and (knock on wood) haven't had any of the nutrient deficiency problems that can arise.

Don't give up! :) Are you set on these particular varieties?

I just checked on the tomatoes again and the color seems a lot more even today. And I'm happy to say that a lot more are finally starting to change with a more even color.

It's the first year with the greenhouse so the dirt may need some tweaking. As for Miracle Grow, I'm anti-Monsanto and anything to do with them but finding nature alternatives are fairly easy.

macky77 I'm definitely not set on these varieties... lol.... I want to try and find a better variety for growing in a greenhouse.... Any suggestions?

i think heat (it was quite warm recently), watering and genetics
plays a role in uneven ripening
i had some 'green shoulders' recently,
due to the heat drying out the greenhouse faster than i am used to

if in doubt pick earlier and allow to ripen indoors,
i have heard this is a fool-proof method for consistent ripening of fruit (at the first blushes of color bring inside)

"Uneven ripening of the fruit with various areas of green to yellowish green on the fruit is called blotchy ripening. The cause is not exactly known but is frequently associated with low potassium (K) and high nitrogen (N) nutrition of the plant"

I don't have a greenhouse, so I can't comment on that front, but I've grown a whole host of toms outside and they do very well.

Applause is my all-time favourite hybrid. It's a really zingy beefsteak and the earliest of any tomato I've ever grown to ripen on the vine (with the exception of cherries and saladettes, of course). I love it so much I'm actually tinkering with it a bit so I can have a stable OP to grow in future. I grew F3 this year. I bought my F1 seed from Veseys, but I think it's available from Stokes, too. I've looked high and low to find out who bred the variety, but can't seem to find that info.

Also grown this year: Black Krim, San Marzano, Roma VF, and Polish Linguisa. The kids chose Juliet and Lemon Boy for their little garden area. They all produced well enough, but I didn't manage to keep up with tying the indeterminates, so they probably could have done even better.

I can't even begin to recall how many varieties I've grown in the past... all the standards you buy as bedding plants around here for sure, plus a couple dozen I've ordered through the mail. I don't grow any of them anymore, not because the plants weren't up to snuff, but because most tomatoes in general are too sweet for my taste. I like a complex flavour that's more acidic.

We garden in-ground. I test my soil in the spring and add whatever it needs. We've been good about working in the homemade compost and grass clippings the last few years, so the soil texture is improving. I add soy bean meal (from FeedRite) and a bit of synthetic nitrogen in the spring if it's called for (less and less each year) and we've been successfully lowering our very alkaline pH (though that's been only recently and the tomatoes were doing fine even before that). I don't fertilize at all over the rest of the growing season.