You may have some Tasks that don't have a set schedule, but there are specific situations that may require the Task to be completed. For example, you may need to spray fungicide after it has rained for an extended period, but there isn't a schedule to predict the weather. However, you can create a Work Order or PM Template, which you can start and assign right after it has rained. 

There are two options when it comes to creating intermittent Tasks. The first is to start with a Work Order Template. As you are completing your Work Order, check the box that says "Planned." This will let the system know that this work order was not created because of something unexpected.

The second option is to create a PM Template without assigning a schedule for that PM. Instead, the next time it rains, you can manually activate the PM. From your PM list, click on the arrow icon to the right, and you will be guided to assign the task.