The initial vision of a constructed space can be maintained as it evolves if the original creators remain involved to help steer changes.
Landscapes in public spaces evolve through multiple influences. A site’s mission, funding, or management can shift this evolution. Community needs may dictate a site’s alteration as well as ever-growing environmental changes and updates in best management practices. Additionally, anticipated replacement of materials due to extraordinary high-use, coupled with technological advances, can influence the maturation of a constructed landscape.
Over time all these influences would make it easy for the original mission of a site to get lost unless the original designers were involved as changes were made. Lurie Garden has had the opportunity to continue to engage with the original designers of the garden as well as with the people involved in the garden, creating a team of stewards of the site’s mission and future.
The garden’s staff communicates regularly with the original landscape architects, Gustafson Guthrie Nichol (GGN), the perennial plant designer, Piet Oudolf, as well as current plant growers and contractors, including Roy Diblik of Northwind Perennial Gardens.
The consistent connection among these parties keeps the space’s initial vision intact while adapting to the forces that are pushing change. This conversation helps maintain the currency of Lurie Garden’s landscape aesthetic, artistry, and historical context as well as its relevance in the public garden, horticultural, and cultural landscape fields.
Keeping all parties engaged and informed of major changes is the responsibility of the Lurie Garden’s director and head horticulturalist. These issues and ideas are presented and scheduled for conversation with the stewardship team. Following discussion, a course of action is determined for implementation by the garden’s staff. Discussions take place via email, skype, and during site visits typically scheduled every other year. While all parties’ perspectives have equal weight, implementation is primarily left to the staff’s discretion based on priority, funding, and feasibility
For those involved in the original design and construction, the opportunity to remain engaged with the evolution of Lurie Garden is an opportunity to understand how a public garden landscape changes over the years.
The site’s stewards’ committed involvement not only allows the garden to be responsive to changes; for those involved in the original design and construction, the opportunity to remain engaged with the ongoing evolution of Lurie Garden is also an opportunity to understand how a public garden landscape changes over timescales of years and decades.
An example of an on-site consultation
At the end of August 2016, the group of stewards convened in Chicago, and each participant was given a map of the garden and a clipboard for a walking meeting to evaluate all areas of the Garden.
Leading the conversation were Laura Ekasetya, Lurie Garden’s former head horticulturalist, and Scott Stewart, former Lurie Garden director and current Millennium Park Foundation executive director. Also participating was landscape architect Shannon Nichol of GGN and plantsman Piet Oudolf who were both a part of the original design team. These individuals bring specialized knowledge and fresh eyes, and they retain clear knowledge of the initial spirit that drove the building of Lurie Garden.
The group’s trajectory through the garden was led by Laura, who brought six years of experience and responsibility of being in the garden daily, interacting with plants and visitors, and maintaining the look of the garden beds. Notable lessons, issues, and points of interests were covered. Problems, successes, changes in the garden, changes in visitor behavior, etc. are shared and discussed.
Lurie Garden is refined, improved, and adapted for the future while still retaining the holistic spatial and experiential qualities that make it unique and enjoyed as a beloved destination space.
Some items on Laura’s list were smaller-scale topics, like a plant that is no longer behaving as originally intended, and others are more significant items, such as a multi-year plan to update lighting.
Each discussion topic and stopping place in a walking meeting like this has a technical and design-related backstory, a decision point for the group to discuss, and an agreement on a potential resolution that will correct or refine the given issue. In this way, as the meeting proceeds, Lurie Garden is refined, improved, and adapted for the future, while still retaining the holistic, spatial, and experiential qualities that make it unique and enjoyed as a beloved destination.
Below are some topics discussed, both small- and large-scale, and the resolution discussed.
Small Scale Topics
The Salvia River
The Salvia River is an iconic, stunning feature of the garden during the first few weeks of June. This 25 ft wide, winding swath of salvia traverses the entire Light Plate. Its great expanse makes it striking when in bloom; but if the area is not managed well when it is not in bloom, it can seem out of step with the rest of the colorful garden just a month or so later. In early 2016, as an experiment, Laura and her team cut back portions of the river after the first bloom in hopes of a second bloom to keep the area active with color.
After the group was briefed on the experiment and the results of the cut-back were viewed, it was decided that cutting back the salvias, mostly toward the middle of the planting, created interest as the eye drifts across the bed of re-blooming salvia to the dark stems of spent blooms. It was proposed that Eragrostis spectabilis (purple lovegrass), Ceratostigma plumbaginoides (plumbago), and late garden bulbs be added to the Salvia River to help this area retain interest throughout the year.
Another small-scale challenge discussed by the group is the favorable growing environment for Ruellia humilis (prairie petunia). The original goal in including this plant in the garden was for it to fill in all the areas where the soil shows between the plants and along edges in the Light Plate and in the Dark Plate meadow. It works spectacularly as a native groundcover or filler plant that continuously blooms from late June nearly until frost.
Laura had observed that the petunia had become too aggressive and had started to encroach into the space of other plants, so she has been experimenting with removing some of it to allow other plants room to grow, which has had great results. It was agreed that the prairie petunia was to be removed in many areas of the Dark Plate. This also allows for additional experimentation with some other plants to act as filler.
Miscanthus sinensis ‘Malepartus’ (Eulalia grass) was a part of the original planting plan for Lurie Garden. While Lurie Garden had a sterile variety, it had become rangy, difficult to manage, and it had become out of scale with some of the plantings. Moreover, a species of this plant has been known to become invasive.
It was decided to remove all of the eulalia grass and Piet suggested Pannicum virgatum ‘Dallas Blues’ (switchgrass ‘Dallas Blues’) as a replacement. This cultivar of our native switchgrass is less aggressive, fits the scale of the garden, and has a beautiful blue-tinge and texture that add to the garden’s overall beauty in the summer, fall, and winter.
Lightening the Palette
Lurie Garden is open from 6 am to 11 pm every day. The staff had become increasingly aware that in low light, the garden tended to disappear in some areas. Adding white flowering plants that are more noticeable in the evening was proposed as a possible solution. As a result, Euphorbia corollata (flowering spurge) and snowdrops were added to the Light Plate. In the Dark Plate, Ageratina altissima (chocolate Joe Pye weed), which is often removed, has been allowed to stay. Additionally, Eurybia divaricata (white wood aster) was added, and the white flowers of the new magnolia trees are added white as well.
Trees in Lurie Garden
It was determined that the Dark Plate could use a few more trees to keep its shadowy theme as a cool, intimate contrast to the warm, open prairie-like Light Plate. The Dark Plate, as Shannon reviewed in the discussion, was designed to offer a place that feels like a romantic Chicago forest edge, thickly planted around the mysterious paths, and partially shaded — a “marshy” experience evoking the original natural landscape of Chicago and the site’s past as the lush mouth of the Chicago River. (Read more about how GGN embedded Chicago’s history in Lurie Garden’s design.)
Several issues were discussed regarding the originally installed trees of the Dark Plate, which are, like the rest of the garden, in planter boxes. Laura presented several declining cherry trees due to root infection and a Cercis canadensis (redbud tree) that turned out to be not well-adapted to the hot summers in the garden.
Shannon recalled for the group the original exhaustive consultation process with local botanists, arboretum researchers, and horticulturalists on the optimal hardiness and informed preferences for various flowering trees for this site. It was valuable for Shannon to compare the past research and best-effort projections on conditions in the tree pits with the physical “answer” or outcome of the diseased tree in 2016. At this point, the group had gained specific insights from the 12-year test of these trees in built roof deck and planter boxes to apply toward the more informed selection of the replacement tree.
The group agreed to choose replacement trees that could better adapt to the site’s known microclimate and planter box performance, while more strongly expressing the design vision for the dark plate of native, wild, and bold-foliaged plants.
The replacements for the redbud and one of the three higan cherries would be North American Magnolia trees. These trees will bring the lush, broad-leaved look of a moist, cool forest to the Dark Plate, as envisioned as a compliment and respite from the bright, open Light Plate. After careful research, Laura selected some magnolia trees which were planted in the fall of 2017 – Magnolia virginiana (sweet bay magnolia) and Magnolia tripetala (umbrella magnolia) which are native to the Midwest. The ‘prehistoric’ look of these trees will contribute to the Dark Plate’s theme.
The last two higan cherries were replaced by black locust Robinia pseudoacacia ‘Chicago Blues’ (black locust ‘Chicago Blues’), that have proven themselves as strong performers despite tough conditions. One of the two Sargent cherry trees in the garden was replaced with Quercus muehlenbergii (Chinquapin oak tree). Its eventual high canopy and wandering, wise branching form will enhance a sense of history and wildness to the Dark Plate, as well as some cool shade for visitors in the summer. The final cherry tree was removed and research is being done to determine its replacement.
Limestone Planter-Bed Edging
Lurie Garden is a rooftop garden, and the plants actually grow in a series of rooftop planters. During their design work in 2000-2004, Shannon and the team at GGN worked to shape the landform and walls of the planters to look and feel more like large swaths of contiguous, “real land” than a series of separate, raised planters. The goal for the garden’s thoroughfares was to make visitors feel like they were walking on a path through a single landscape rather than between two, separate planters.
The original intent was for the planter walls alongside pathways to be as invisible as possible, to make the garden around the path feel larger and to keep the focus on Piet’s perennial compositions rather than on the raised beds themselves. To do this the garden soil level would need to reach the top of the walls so the plants would have the opportunity to cascade over the walls. There was a miscommunication during the 2004 installation, and the soil was not filled to the top of the planter walls, thereby exposing the wide profile of the wall meant to be concealed by soil and plants.
In some areas, the garden has grown to hide the exposed walls anyway, so the desired effect is still achieved but in many areas, the wall remains exposed. Filling all exposed wall areas to meet the original specifications may prove too difficult, but many will be addressed. The Lurie Garden team will need to special-order additional fill soil from the original source, to be mixed to match the existing soil in order to move the garden closer to the edges where possible.
Shannon also noted that since seeing that the soil was not originally installed to the level shown in the specifications for these limestone planter walls, GGN has developed more backup graphics and callouts in their planting construction sheets to explain to the soil-installers the role of soil level in these types of concealed-retaining-wall details.
Lighting the Garden
Some of the garden’s lighting has needed updating due to technology improvements, a shift in the desired ‘mood’ given by the lights, and changes in foot-candle requirements.
One challenge of the original lighting placement was to avoid placing light poles in the Light Plate while keeping in line with rigorous lighting (foot-candle) requirements at the time. To achieve this, lights were affixed to the steel armature framework of the Shoulder Hedge to light the paths bordering the garden, and lights facing the Light Plate were mounted to tall dark poles in the Dark Plate, which were to eventually blend in with the grove of tree trunks planned for that half of the garden.
The group discussed four things that had changed since the original lighting design:
- The lighting requirements (foot-candle) for the Light Plate have significantly decreased since the original design. Lurie Garden has not needed the amount of light cast from the downlights atop the poles in the Dark Plate.
- Lighting technology and efficiency have greatly evolved since the early 2000s – Much better lamps have become available require less maintenance, are more energy efficient, and have improved color options.
- The trees of the Dark Plate, which were originally designed and expected to grow into a tall grove that would help conceal the tall poles, have been partially removed over time and left the tall poles particularly conspicuous in more open space.
- The Modern Wing of the Art Institute of Chicago now lends ambient light and contrast into Lurie Garden, further decreasing the need for the strong light source to wash across the Light Plate.
- The series of “can” uplights in the Dark Plate, which were designed to be installed hidden in the ground but were erroneously installed above-ground, have become eyesores in the early spring because the trees that camouflaged them initially have been removed.
The group all agreed that change is necessary for the lighting to adapt to the above factors. As a result, two of the four light fixtures atop the tall Dark Plate fixtures have been removed as well as all of the “can” uplights. Additionally, the remaining lamps in the garden were retrofitted to enable them to accept LED bulbs to provide a softer, warmer, less glaring output and to avoid emitting more light than is currently necessary.
The Lurie Garden team will decide on some future solutions to softly light our trees for evening strolls, as originally envisioned in the soft and romantic Dark Plate. The team noted that the garden is open every day until 11:00 pm, and popular for evening strolls, so lighting is important to the appreciation of our garden at night.
Continuing the Process
Piet Oudolf and GGN’s Shannon Nichol return again in early October 2018 to walk the garden. This time the group will include Yaritza Guillen, Assistant Horticulturalist and previous GGN Public Garden Apprentice, as well as Peter Slothower, Lurie Garden’s current GGN Public Garden Apprentice. The seasoned stewards will continue their work evaluating the garden’s conditions and moving it forward while Yartiza and Peter will begin to learn this process of continual experimentation and editing.
The basic units of the Lurie Garden landscape design—its landform, planting plates, and border hedges–are strong, powerful elements that provide context within which change, evolution, and adaptation can be discussed.
The garden is based on a strong conceptual and physical foundation. Over time visitors, climate change, technology advancements, and culture reveal where changes are needed. A team attuned to the garden’s evolution allows Lurie Garden to act responsibly and maintain its relevance to the industries of garden design and landscape architecture, to the environment, and to the public it serves.
Multiple authors contributed to this article, including GGN’s Shannon Nicole and Lurie Garden’s Laura Ekasetya, Scott Stewart. Edited by Jo ana Kubiak.