Forest Gardening: Soil building
Denver, ‘Queen City of the Plains’ is forested; in central neighborhoods like Congress Park, we are fortunate to live under an assortment of beautiful mature trees. Just before moving back home, we were living in Maine and had the opportunity to learn from the great seed steward, Will Bonsall. Inspired by forest functioning, he structures his gardens with vertical layers; trees, shrubs, forbs and roots…and promotes using leaf litter as an excellent form of nutrient building in soil. He says that the only sustainable form of ‘mining’ is to work with trees; their roots tap nutrients from deep in the ground, pulling them up and infusing them into their leaves. The transformation into rich soil is accomplished after the leaves fall by decomposers, including young caterpillars who offer essential soft proteins for spring’s baby birds. We have too many leaves to process in our small, urban garden, so I rake my elm leaves up first, deposit them in the green bin, then use the nitrogen rich oak leaves which fall later, and work those into the garden.
Make it neat & pollinator friendly
In our urban environment, presentation can be important. As an artist, I approach a plot of land with attention to creating a variety of color, texture and line. Unlike a fixed painting, time becomes an element that brings dynamic change through the seasons. In fall, I showcase the variety of plants by shaking fallen leaves off their tops, letting them settle around their bases as habitat-rich mulch. Leaves don’t need to be left where they fall to be helpful. Tuck them under bushes and around the bases of trees to retain moisture and suppress weeds. Shredding the leaves makes them look more refined within flower beds, and the smaller bits break down faster into soil. The Denver Botanic Gardens at Chatfield takes the approach of tidying up the front edges of their entry gardens and transitioning interior spaces to more ecologically friendly (and wild) mesh of fallen leaves, old stems and seedheads. This appeases visitors who expect to be greeted by formal looking ‘gardens’ while being sensitive to the ecologic needs of our urban spaces. Just remember to also hold off on the spring ‘cleanup’ so you don’t disrupt the cycle of life you’ve worked to create.
Echinacea: inviting wildlife to your garden
It’s important to leave seedheads standing through the winter so that plants can regenerate, seeds can feed the birds and stems can offer homes to solitary bees. According to the Audubon society, birds LOVE echinacea seeds and are messy eaters, flicking seeds about as they feed. These seeds produce the next generation of plants. If you like the wild look of a meadow, leave them interspersed with other regenerating natives. We have a 2’ dry strip of ground along the side of our house which is perfect for a mini meadow of wildflowers and native bunching grasses (winter hibernation for bumblebees!) For more formal beds, you can match leaf to emerging leaves and transplant seedlings to bunch them around the mother plant as they emerge in spring. Plant successive blooms so that pollinators have forage through the season, in turn providing forage for insect eating birds. Goldenrods and Asters are a classic pair of late bloomers that offer pollinator support through the autumn, then provide nutrient dense seeds for migrating songbirds. I’ve never understood the visual appeal of a cut out garden instead of maintaining the variation of what is growing there. Who doesn’t like the added adornment of songbirds who feel more at home in a standing garden where they can find food and shelter into winter? Pronounced seedheads interspersed with evergreens and berry producing plants layered under our mature trees make for beautiful landscapes that support wildlife in all seasons.
Find Will Bonsall’s Essential Guide to Radical, Self-Reliant Gardening on www.chelseagreen.com
Learn more about #leavetheleaves at https://xerces.org/leave-the-leaves
Denver’s Audubon chapter: https://denveraudubon.org
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