could be they are not getting polinated. do you have plenty of bees or other polinators around, if not you might have to get a small paint brush and help out.. good luck, I have 10 black krims growing, I love them..

Robert.

I don't get much production from heirlooms. I tried Black Krim again this year for the third time and got one tomato. I won't bother with that variety again. So far Cherokee Purple is the only heirloom worth repeating for me. That said, next year I'm going to try Indian Stripe and give Marianna's Peace another chance.

here is some more info

Here is a link that might be useful: Tomato blossom drop causes

I really like Black Krim. The plants of course do not produce as heavily as some hybrids but pretty decent for an heirloom and thus worth their space. I have a Kellogs Breakfast plant that has only a couple fruit that will make it to ripe and some smaller ones. I think I will look for a more productive heirloom yellow/orange for next year.

My BK is in a raised bed. It's been horrifically hot here for most of the past 10 weeks and none of my toms (about half heirlooms) are getting as much water as they'd like. Despite that, they're doing well and almost all are setting fruit well. The BK is easily the largest of them all -- I say quite seriously that it's trying to take over the world! It's set more fruit than any of the others (except Juliet, which is small-fruited).

Because my notes said BK would top out at 3-4', I put it in one of the ancient wide wire ring supports, with Florida weave-type twine to about 4 1/2'. I've got the BK growing sideways along the Florida weave and it's ready to eat its neighbors....

Missing, just out of curiosity what are your overnight lows?

This was my first year to grow heirlooms, and Black Krim was by far the biggest producer. The tomatoes were big and delicious, though there was a lot of splitting, which healed, on the shoulders. They have all shut down in this heat for the last few weeks, except Black Krim, which has set a few fruit even in this. (Night lows have been in the low seventies.) I have fertilized (thanks, natal) and am hoping for more production when it cools down this fall. I will definitely grow it again. Mine is a big tomato, probably 6.5 to 7 feet high right now.

Donna, my plant got really tall too. Our night time temps have been in the high 70s/low 80s for the past couple months. All of my tomatoes pretty much stopped producing by the end of June. Still have green tomatoes on the Sun Gold, that occasionally ripen, but all of the remaining plants are pretty much just sitting there right now. I pulled most of them, but left 5 or 6 just to see if they'd start producing again when the temps fall.

natal, I'm in a valley in the mountains. The overnight lows I've noticed on the weather forecast have been high 60s to low 70s. No hot, stagnant nights this summer, despite the above average number of 90 degree days.

With overnight temps above 75, that's got to be why you're not setting much fruit (I'm surprised you're setting any, since pollination supposedly fails above 75).

Unfortunately I can't compare my BK's behavior to past years, since the only other time I planted one, Late Blight killed it in July. And everything else.

Thanks for all the input! It would seem that I'm not the only one with troubles--There are plenty of pollinators, but no big night temp drops -- so maybe it is the heat--Baltimore has been brutal this summer-- maybe I'll just stick to hybrids--

Jacewell, don't give up on heirlooms. We don't all have a lot of luck with them, but it's worth it to keep trying different varieties because you're bound to eventually find one that's a keeper. That's how I feel about Cherokee Purple. And even though I get frustrated with new heirlooms I trial each year I still do it again the following year. Hope springs eternal. ;)

Thanks for the encouragement--there is still time here in "Charm City" (aka Baltimore LOL)so I'll keep hoping