Abstract: A timer has as at least two timing intervals, at least one of which is switchable between different preset intervals by the user, between which tasks are to be performed by a user. Upon the expiration of each timing interval, the user is alerted that a task is to be performed. A display panel indicates the number of days remaining in one of the timing cycles and may temporarily be switched to indicate the number of days remaining in the other timing interval. A particular use for the timer of this invention is to remind a user to service a humidifier. Another particular use is to remind a user of chores to be performed to maintain indoor or outdoor plants.