Yellow tomato leaves signs 👇 Yellow leaves can be caused by a lot of things. 1. Too much nitrogen causes burning and yellowing on older leaves 2. Too little nitrogen causes yellowing of leaves 3. Cold temps can cause yellowing of leaves 4. Too much water (aka rain) can cause yellowing of leaves It's important to know your soil and conditions. In my case it's simply rain and cool temps, this will right itself this weekend and there's no need to take any action. These tomatoes don't need an egg p