December brings short days, cold wind, snow and mixed wintry precipitation, and the first day of winter. It is one of the quietest months in the garden, at least on the surface. However, potential for the next growing season is in plant crowns, buds, seeds, pupae, overwintering adult insects, larvae, eggs, nests, and hibernacula.
For ecological, aesthetic, and practical reasons, we do not trim the garden beds in the fall. Fall trimming removes dormant life that overwinters on, or in, standing plant material. Removing seeds, plant rosettes, leaf litter, and dried stems eliminates habitat—food and cover—for wildlife active through the winter months. When seed heads are left standing, seeds fall continuously and work into soil with precipitation and freeze/thaw cycles, ensuring plant reproduction.
Branches, stems, persistent seed heads, and grasses provide color and form in the winter garden. In addition to the wildlife they attract, these features are described as “winter interest,” especially in combination with snow, ice and hoarfrost. Consider how you will view the garden in winter—from indoors or from paths or openings.
At the Arboretum, leaving the garden beds untrimmed also allows our many visitors to see where the plants and paths are when we have snow cover. This reduces trampling, compaction, and inadvertent damage, which can harm plants and soils even in winter.
Our garden tasks this month are: data entry, pruning, setting seed trays outdoors for stratification, planning for plant orders, and scheduling tours and presentations for the next growing season. This is also a good time for reading, research, and finding resources that address gardening questions and broader related issues.
Thanks to one of our garden volunteers, I recommend this book for families. The Lost Wordsby Robert Macfarlane and illustrator Jackie Morris is based on a set of words related to nature that were dropped in the 2007 revision of the Oxford Junior Dictionary. These were replaced with other words that children are encountering frequently in their lives, mostly related to technology. The dictionary reflects the times but not what children need to name and know in the world if they are to understand and love nature and language. Share this book.
My other recommendation this month may seem far afield, but it overlaps with native plant gardening in concepts and some practices, especially considering a landscape scale. Chris Helzer (Director of Science for The Nature Conservancy in Nebraska) shares observations and exceptional photos frequently on his blog, The Prairie Ecologist. In a recent post, Creating Wildlife Habitat on Great Plains Ranches, he describes a range of ranching practices and their ecological effects. Topics include: timing of grazing (or disturbance), patterns and dynamics of species diversity, wildlife habitat preference and uses, and quick assessment of sites. In summarizing the qualities of a healthy grassland, Helzer quotes Wayne Copp, a Kansas rancher, who says that every prairie should have color, movement, and noise. Color reflects plant diversity as well as wildlife presence, and movement and noise reflect a healthy, diverse biota.
May your garden have color, movement, and noise in all seasons, even if muted and muffled in winter as plants and many animals lie dormant. In the subdued and quiet days of December, let’s read!
—Susan Carpenter, native plant gardener