Your mower is a mulch factory and you didn't even know it.
Run it over the fallen leaves, spread the shreddings across your beds, and walk away. They'll feed the soil as they break down, insulate roots through the cold snaps, and shelter the overwintering pollinators sleeping in the leaf litter.
One Pacific Northwest caveat, learned the damp way: don't let them mat into a soggy felt over the crowns of your perennials. Our winters will turn good intentions into mush. Shredded and fluffy, not whole and matted — that's the whole trick, and it's free.
And on the lawn: wait until around Easter — or Ramadan or Passover, whenever spring actually arrives — to aerate and reseed. Go with a fescue blend rather than straight annual rye, give the seed three full weeks to germinate, and mow as high as you can so the roots drive deep. Lawns don't really want to be here, given our pH and soils, but we can make them as nice as possible. No chemicals needed.
