Eric Rodriguez, Director of Horticulture, describes the wonders of wintertime gardens and preparation for Spring Cutback.
What is especially unique and noteworthy about the garden in wintertime?
The winter garden is just as important as the garden in any other season. Piet Oudolf’s artistry of shape, texture, form, chiaroscuro–these are elements that are arguably even more pronounced in winter than during other times of the year, and he purposefully incorporated seasonal interests, such as seed heads and the color of fallen leaves into the design.
All textures and shapes are more prominent; plants shadows and silhouettes cast against a snowy bed and there is a contrast of straight lines and geometry of adjacent architecture with the more “random”, organic shapes of the plantings. There is an infinitesimal diversity of monochromatics: so many shades of brown in leaves, branches, seed heads, dried fruits.
I think all of the sumac species have such incredible architecture in winter. I’m a fan of the seed heads of the blackberry lilies (Iris domestica) in the Meadow Walk. Another early spring delight are winter aconites in the Washington Grasslands, with their cheerful yellow buttercup-type flowers that are barely tall enough to notice unless you’re specifically looking for them. The dawn viburnum is also currently blooming..
How will the Horticulture team prepare for Spring Cutback?
The gardeners are actively researching, learning, and planning. Staff members are, sharpening and replacing tools, learning new skills and softly preparing for the spring planting season. Learning is a lifelong activity for a horticulturist, we know so much less about plant life than we think we know, even as seasoned professionals
I think of the gardens as “five-season” because it chronologically centers the growth of the plants. “Five-season” speaks to the transition between one growing year to the next. So, as we transition between the dormancy and death of the plants from the 2020 season, the “fifth season” is the transition to the beginning of the active growth cycle, the beginning of the 2021 growing season.
Winter is when we typically prune all of our trees for structure, safety, and resilience in a landscape that is under constant environmental pressures of heat, cold, extreme winds, and high visitation. During winter, as well as year-round, we prune trees for the “3 Ds”: death, disease, and damages. Of course all of that woody material needs to be composted, so organic debris management thirty feet in the air is a major undertaking as well!
Beyond art and aesthetics, we’re science-driven, and are always refining our practice through a process of inquiry, research, hypothesis, experimentation, observation, implementation, and presenting/sharing our findings. We trial new techniques in the field to improve resilience of the collections.
What will be different about this year’s Spring Cutback?
In recent years, we have started evolving the practice to leave more organic matter in the beds, such as leaves, whereas we used to carefully rake it all out. Also, we have strategically not cut certain species of plants until the weather gets warmer for native bees that make use of the hollows of stems. Currently we look for stems that are approximately the diameter of a coffee stirrer, and we use an actual coffee stirrer as a measurement tool!
Recognizing the uncertainty of the ongoing pandemic, and the concerns of more contagious variants of COVID-19, we have additional safety protocols this season.To cut back the grasses, you need at least two people standing within a foot of each other, face to face, and we have so many grasses! So, with much sadness, we must scale back our volunteers’ involvement this year, for both the safety of the gardeners as well as our volunteers.
Immediately after Spring Cutback, we schedule the start of the irrigation system for the season in the magic window period between the last hard freeze, but before the first truly warm days in Spring. We have expanded the footprint of the system in recent years, but we continue to extend it into areas with little or no irrigation lines, so immediately post-Cutback is the ideal time before the plantings grow too tall and dense.
What are the signs of spring a visitor would see on the High Line?
There is active growth happening underneath the soil: roots anchoring down; flower stalks starting to emerging from bulbs; ground-nesting bees in dormancy waiting on environmental cues to emerge; cells dividing on the microscopic level, strands of symbiotic fungi stretching through particles of soil; and seeds carried by winds and animals to new locations where new seedlings will establish. Our plants “migrate” through the park and pop-up in new locations unexpectedly, recycling nutrients from plants back into the soil.
Snowdrops under the flyover are my go-to species to remind myself that spring does come after winter, no matter how the weather might deceive us, so they’re a great harbinger of spring.
I think there are different experiential indicators: sights and sounds of increased bird activity; fragrance of the spike winter hazel, Corylopsis spicata, in the Chelsea Thicket; Spring bulbs emerging, tucked away under concealing matrix layers of grasses and other perennials; and the tone of light–the intensity of more full-spectrum light from the moodier oranges and yellows of fall and winter.
Photography by Liz Ligon and Steven Severinghaus.
Special thanks to our Presenting Green Sponsor TD Bank for their generous support of the park’s horticulture and sustainability practices.
Additional support for Horticulture on the High Line is provided by Greenacre Foundation.