Should I cut back and rake my fall garden?

#leavetheleaves — *The Xerces Society for Invertebrate Conservation is an international nonprofit organization that protects the natural world through the conservation of invertebrates and their habitats.*

As summer fades into autumn, the leaves begin to fall and many plants begin to fade. Embrace the natural beauty of the landscape and put your rake and secateurs away!

BROWN IS THE NEW GREEN!

Conventional landscaping popularized the practices of “if it’s brown, cut it down” and “rake it clean, keep it green” in order to keep landscapes looking vibrant, green and tidy for as long as possible. In contrast, ecological landscaping recognizes the beauty of fall and the important role that fallen leaves and dormant perennial stems play in cycling nutrients and providing habitat for pollinators and other wildlife.

Benefits of leaving leaves and stems

Habitat:

Many insects overwinter as adults, larvae, eggs or pupae and require shelter in order to survive the harsh cold season. When left in their natural state, gardens can provide plenty of nooks and crannies to help wildlife complete their life cycles. For instance, the eastern comma and fritillary butterflies hibernate in adult form under leaves or bark, while numerous bee species are cavity-nesters and spend their winters inside perennial stems.
Throughout the winter, snow will be caught by the standing stems and build up to provide a layer of insulation on top of the hibernators in the leaf litter.
Butterfly and moth cocoons and adults, firefly larvae and bumblebee queens seek shelter in the fallen leaves as temperatures begin to drop. If the leaves are raked and bagged for yard waste, these animals are thrown out too.

The leaf layer is the world’s butterfly nursery!

Nutrient Cycle:

Plants help feed themselves with their own leaves! These leaves contain the nutrients that the plant needs the following year.
During the growing season, nutrients are drawn from the soil and stored in the foliage of plants. In autumn, nutrients are returned to the soil when the leaves fall to the ground. This natural cycle of nutrients is an essential process for plant, soil and microorganism health.
If the plants can’t access the nutrients they usually supply themselves with, they won’t have the strength and vigour to fight off diseases and insect infestations. Allowing the plants their natural processes will contribute to their long-term health and resiliency.

Leaves are the best mulch!

Chickadee eating plant seeds in winter — *©P.Bannick*

Birds:

In natural ecosystems, perennial stems are not intentionally cut down. They support wintering birds by providing food (seeds, larvae hidden in galls and stems, insects in the leaf layer), and shelter from cold winds and snow.
Birds eat aphids in the fall, seeds in the winter and caterpillars in the spring - all of which can be provided by our year-long gardens.

Gardens can feed birds all year long!

Beauty:

A well designed, ecologically friendly landscape will include late season blooms that provide essential food for late season pollinators and wildlife, like migrating monarchs and hibernating eastern commas and bumblebees. These plants, such as asters, goldenrods and lobelia, look stunning when highlighted next to the fading foliage of ferns, grasses, bellworts, milkweeds, aralias, anemones, etc!

*New England asters and fading Canada anemone. ©A.Brennan*

Fall garden tasks

Contrary to conventional recommendations of “putting the garden to bed”, there really isn’t much that should be done to the fall garden.

Leaves can be cleared from gutters, walkways and around foundations and placed in gardens to help insulate plant roots and provide habitat for wildlife.
When it comes to lawns, rake once in the middle of leaf-falling season and then leave the rest of the leaves where they lay. A very thick layer of leaves can smother your lawn, but a thinner layer will break down and provide nutrients and aeration to the grass. Consider shrinking your lawn next season and replacing it with native plants.
Remove stems from any invasive flowering plants (ex. Himalayan balsam, goutweed, dame’s rocket) and follow disposal recommendations. Consider removing these plants next spring and replacing with native plants.
Cut stems of plants that will end up falling into your walkways to random heights between 8 and 24 inches (the optimal heights for different stem nesting bee species).
If you have a small space and some aggressive self-seeding plants, cut some of the stems (8-24”) to reduce next season’s spread.

When you look at the changing colours in your landscape, think of the changes in the deciduous forest - your landscape is a smaller version of the forest and supports life in the same way.