Leave the leaves that fall into your garden!
Why, you might ask? So many reasons! For one, they make excellent mulch and help protect your landscape and garden beds during winter rains and wind. They provide insulation and also help keep the weed populations down. They help support microbial growth and mycelium (healthy fungi). These microorganisms help support worms, birds, bees and many of our local habitat critters. When we improve the soils, we help control run off of nitrogen that can pollute our rivers. Our ecosystems are a delicate balance, and leaving the leaves is just one simple step we can take to help the balance of carbon, nitrogen and phosphorus in out soil. And perhaps most importantly… Its so much easier that raking them all up. Gardening can be quite easy when we follow a more natural flow.
Biomimicry is when we mimic natural processes in our gardening methods. This is applicable to the reasoning of why we “leave the leaves.” As in a forest (and much of the Portland region is quite similar to a woodland forest), the leaves fall from deciduous trees during autumn to layer the forest floor. The rains come, and slowly the leaves compost over time, adding nutrients from leaf mulch. Biomimicry is one way to define this method of gardening. It is a concept used in permaculture, where we take notes from the natural world, follow a more natural way of doing things to partake in the traditional wisdom of the Earth.
If you want to go a step further, consider collecting leaves from your neighbors. Adding leaves to areas you want to build a planting bed is an easy way to add fertility and improve your soil quality. For example, if you have sandy soils, leaf mulch is a great way to make your soil retain more moisture. On the other hand, if your soil is hard and clayey, leaf mulch, just like any other organic matter, will help to make your soil more fluffy and delicious (to your plants, earthworms, beneficial insects etc). As with any type of mulch, leaf mulch is a great way to protect your plants over the winter. Just be sure to pull the covers back in early spring so your plants know its soon time to wake up again as the sun returns.
If you’ve left the leaves over your landscape, in the early spring you can rake them up, but this is not necessary, they will continue to do their job of adding to your soil quality. I often mulch over the leaves, creating a protective layer for my perennials and shrubs. Or, I add them to my compost bin. Ideally, keep one bin exclusively for leaves and over time you will have the richest composted leaf mulch imaginable.
A Winter Meditation
This year consider leaving the leaves and watch them pile up in your yard… all those pretty colors, whirling and dancing around the yard. It is an excellent meditation for sunny or rainy afternoons!