too hot, put a fan on them.

Hi,

Tomato blossom drop is actually a pretty common problem. It is mainly due to either too high or too low of temperatures. Stress can do it too so make sure you give them enough water, especially during the hottest time of day. Also, I've noticed if you do not get enough air movement or you don't shake your plants often enough to help pollinate them, the blossoms will drop. Make sure they are being pollinated.
Hope this helps!

I use a fine spritz of water into each flower, sets every time.