Two factors are most important in determining when to do a fall clean up: daily weather and seasonal timing. Regarding the weather, check the forecast for a warmer day when there is little to no wind. Raking on a calm day will ensure your leaf piles don’t get blown away with heavy wind. Regarding the time of season, you should wait until all the leaves have fallen off the trees on and around your property (including your neighbors yard.) This will likely be some time between late October and mid-November. Read more about when leaves tend to fall in my blog A Guide to Understanding Seasonal Leaf Drop.