One of the easiest ways to cut down on garden and lawn maintenance is to switch from grass to moss, ivy or clover. Moss grows quickly (though it can take a few seasons to come in fully) and helps soil retain moisture. Bloedel Reserve devotes an entire garden to the lushness of moss (above). Moss thrives in low light, high moisture areas like Washington, though temperatures do not tend to affect growth other than to slow it down during hot, dry periods. In fact, moss usually remains dormant when dried out, and revives when water returns.
Details & Ideas: Replace patches of dead grass or use moss to complement other shade-loving garden life. The bases of maples, oaks and ash trees are great for moss, though it doesn't much like conifers. Fern moss is best for high-traffic areas, while cushion moss is ideal for planting beds.