When the temperature outside is 92°F or hotter, the tomatoes will drop their flowers (blossoms) and will not set any fruit. This is called Tomato Blossom Drop and is normal for a tomato to do. Basically they self-abort their blossoms. Why? Because they want to survive. They will continue to produce new blossoms and once the temperatures is BELOW 92°F, they will start to set fruit from the blossoms.
What can we do to prevent blossom drop? Nothing. We really are at the hands of mother nature. The funny thing is once they do pollinate (tomatoes are self-pollinating and wind-pollinated and don’t need pollinators) and they produce baby fruit, they do fine when it’s hot-it’s just while they are trying to set fruit that the temperature is critical. There is also a low temperature where they will drop the blossoms, but we don’t have to worry about that here.
Last year we had 3 months of intense heat with everyday being 92°F or warmer and the blossom just couldn’t set fruit. Finally when the monsoons came mid-August (which is one month later than normal), and it cooled down, they were able to set their fruit. Luckily for us we had a long fall and were able to harvest before we got a freeze. So don’t despair, they will set fruit from their blossoms when the time is right. Hopefully the monsoons will come in July. So for now, just surrender and chill out (if you can).
Just out of curiosity, is this true with determinant tomatoes too? Will they drop blossoms their blossoms if not pollinated and then re-set when it cools? Or are you just out of luck for that year?
Sylavia-It’s true for all tomatoes! They drop their blossoms not because of pollination (because they self-pollinate) but from the temperature being 92 degrees or higher. As soon as the temp drops (like right now) and they put out blossoms, they will set fruit. Hope we keep the cooler weather for awhile!
Thanks for your post. Now that it’s cooler my tomatoes should start putting out fruit.