4. Blossom drop.
Tomato Troubles
If the blossoms drop off before they’re pollinated, you can probably blame the weather. Tomatoes need nighttime temperatures of 12 to 24 degrees Celsius when they are in bloom. As well, any temperature over 40 Celsius for more than 4 hours will cause the blooms to abort. For cold weather, use Kosy Coats. For hot weather, keep the tomatoes watered and filter the sunlight that hits them. If you run into an extended hot spell, though, you may not be able to save them.