Or they can be composted for use next season. Light layers of leaves on the lawn can even be broken down with a mulching mower and left on the lawn. They provide a free application of fertilizer and lots of organic matter. You don't want them to sit on the lawn too long and smother the grass. Otherwise, there aren't any strict rules as to when you rake.
Some people like to do it in stages as the leaves fall.
Others prefer to wait until most of the leaves are down. If you plan to use your leaves for mulching plants, just be sure you don't apply the mulch too early. If you're a gambler who loves to take risks, you might even try waiting until the timing is right to rake and mulch at the same time. Perennials Lots of people are asking questions about moving perennials right now. This is O.K. for most plants but not iris and daylilies.