Hi @AppleCore, thanks for reaching out.
To cancel/delete a Watering time, simply go into your watering times menu. Assuming you're running iOS, tap and swipe to the right. If you're running Android, just click and hold the watering time you wish to delete. A red "delete" button will appear to remove the watering time. Tap on it to confirm and you're all set!
Hope this helps. Let us know if you have any other questions.