The different types of banana peppers look very much the same and, therefore, it is hard to tell them apart at first glance. There are some differences between sweet banana peppers and hot banana peppers, though, so if you learn what to look for you will easily be able to identify them and avoid any unpleasant surprises when biting into one. Check your peppers carefully, especially when the peppers are first growing for the best results.
Look closely at the peppers once the fruit starts growing on the plants. Sweet banana peppers will grow out from the plant and up; though when they are larger, they will hang down due to their weight. Hot banana peppers will hang down from the beginning. Once you know which is which, place a plant tag in your garden so you can tell them apart.
Examine the color of the peppers. The hot banana peppers, also commonly called Hungarian wax peppers, tend to be a darker green than the sweet ones before they are completely ripe. As they ripen, both will turn various shades of gold and orange and will eventually turn red. If you put two of the green peppers side by side you should be able to tell them apart fairly easily.
Cut into a pepper that has already been harvested. Smell the pepper or take a small taste of it. Sweet banana peppers will not be overly spicy. Hot banana peppers will have a strong, spicy smell and a hot taste to them. Keep all peppers from the same plant together so you will know which are which after you have tested one of them.