Archives For Michael Jesiolowski

Why did five Midwestern horticulturists hike through the oak-hickory forests of the Missouri Ozarks? And why did we need a desiderata? The first question is easy—we were on the trail of specific wildflowers and woody plants to preserve and add to our collections.

Collections trip horticulturists Mike Jesiolowski, Tom Weaver, Josh Schultes, Kelly Norris, and Steve McNamara

Collections trip horticulturists Michael Jesiolowski, Tom Weaver, Josh Schultes, Kelly Norris, and Steve McNamara (left to right)

In a trip funded by the Plant Collecting Collaborative (PCC), a consortium of public gardens, Tom Weaver (horticulturist, Dwarf Conifer Garden) and I (senior horticulturist, Entrance Gardens) joined Kelly Norris (the trip leader) and Josh Schultes of the Greater Des Moines Botanical Garden, along with Steve McNamara of the Minnesota Landscape Arboretum. Before we left, our desiderata—or essential list of desirable plants we would target—was developed, based on what plants our gardens deemed important for conservation, to fill a gap in our collections, or add beauty to our display gardens. And of course, we had the proper state and federal permits in hand for seed collecting. The six areas that we explored were typically oak-hickory forests, which opened up to rocky-soiled glades and provided for plentiful opportunity for collecting wildflowers. With an eye for distinct plant material and genetic diversity, we roamed through the uneven Ozarks terrain, but we weren’t tied to our wish list—we also found a couple of surprises.

Glade opening at Roaring River State Park

Glade opening at Roaring River State Park

Since seed-grown plants are reproduced sexually through pollination, via wind or insects/animals, they are genetically variable. A variety of genes can give each plant the best chance to exhibit a specific phenotype, or physical appearance, and better adaptability to survive pests and diseases. Where seeds are collected could have significant implications on whether a plant can survive in a given environment or not. For instance, we collected seeds of Echinacea paradoxa (yellow coneflower) from its northern most growing region, in Ha Ha Tonka State Park in Missouri. Selecting seeds of Missouri provenance gives this wildflower a better chance of survival in our region, rather than if the seeds had been collected in Texas. Plants that have a different phenotype from what we commonly observe in northern Illinois were of special interest to us. Fruit from Diospyros virginiana (common persimmon) was collected on a 4-foot-tall tree in Mark Twain National Forest because it is unusual to see fruit on a tree of such short stature. In a similar fashion, Symphoricarpos orbiculatus (coralberry), was collected from the Big Buffalo Creek Conservation Area, after we all remarked at the stunning ornamental quality of the fruit display.  

Yellow coneflower (Echinacea paradoxa)

Yellow coneflower (Echinacea paradoxa)

Persimmon (Diospyros virginiana)

Persimmon (Diospyros virginiana)

Josh Schultes examines some holly (Ilex decidua) for collection.

Josh Schultes examines possumhaw holly for collection.

In some cases, we came across desirable plants, but they had already dropped their seed for the year, or simply didn’t produce any due to drought-induced stress. With the aid of GPS, we marked these areas so future explorers to the Ozarks are aware of these plants for their potential collections. For example, Boyce Tankersley, the Chicago Botanic Garden’s director of living plant documentation, was a part of a team that collected in many of these same areas in 2005; their field data was helpful in our search.

Dotted blazingstar (Liatris punctata)

Dotted blazingstar (Liatris punctata)

Although the Ozarks region experienced a late-summer drought that negatively impacted seed production in some instances, we were still able to make 71 collections from October 12 to 16. Our seeds will be grown in our plant production greenhouses. Once they achieve a certain size, they will be distributed to PCC members and planted in the Garden. I am ecstatic to cross Liatris punctata (dotted blazingstar) off the desiderata for use in my gravel garden project in parking lot 1. The seeds we collected should be ready to plant in these beds in two years.


©2017 Chicago Botanic Garden and my.chicagobotanic.org

What comes to mind when conceptualizing a new garden design? Color? Absolutely. Soil and sun conditions? That’s a given. Texture? Sure thing. Two other components of plant selection that are of utmost importance are adding biodiversity and sustainability. Both of these elements are omnipresent in gravel gardens.

The origins of gravel gardening are rooted in Essex, EngIand, via Beth Chatto, Cassian Schmidt at the Hermannshof Garden in Germany, and Roy Diblik of Northwind Farm in Wisconsin. I was introduced to gravel gardens while I lived in Madison, Wisconsin. Not only were gravel gardens featured at Olbrich Botanical Garden, but they were also on display at my previous place of employment, Epic Systems, in Verona, Wisconsin. Jeff Epping, the director of horticulture at Olbrich, established the gravel gardens at both Olbrich and Epic Systems, and has been very supportive in my mission to bring these types of gardens to the Chicago Botanic Garden.  

The heavy, clay-laden soils of the Chicago area are infamous to anyone who has gardened here. No one escapes the frustration the water-retaining properties of these soils causes. Midwestern gardeners often amend the soil in their home gardens. But amending soils in garden beds each season to improve plant health and drainage can also be an expensive endeavor for the home gardener.

The first step in prepping the beds: removing the top layer of soil.

The first step in prepping the beds is removing the top layer of soil.

This season, as a trial, we are converting ten island beds in parking lot 1 to gravel garden beds. These beds are covered by 4 to 5 inches of pea gravel. The gravel allows plants to grow in sharp drainage, which is a very desirable attribute when growing many native prairie plants or other dry-loving plants. Ours include coneflower  (Echinacea paradoxa), ‘Siskiyou Pink’ beeblossom (Gaura lindheimeri ‘Siskiyou Pink’), and ‘Red Rocks’ beardtongue (Penstemon x mexicali ‘Red Rocks’).

The key to establishing the plants in a gravel garden is to prevent the root balls from drying out until they have a chance to root down below the gravel layer. This means watering new plantings daily, or even twice daily if weather conditions dictate. Although a significant commitment to watering is required up front, watering can be reduced six to eight weeks after planting, and nearly eliminated after two years. In fact, with the exception of times of extreme drought, no supplemental watering was necessary for the gravel garden beds I managed at Epic Systems.

Gravel garden plantings include succulents and drought-hardy plants.

Plantings include succulents and drought-hardy plants. They will need careful monitoring at first, but once established, this bed will be a beautiful, low-maintenance garden.

Another benefit of growing plants in 4 to 5 inches of gravel? A significant reduction in the number of weeds! Since no soil exists in the top 4 to 5 inches of the bed, weeds don’t have a chance to root in. Maintaining this “sterile” environment is a matter of simply making sure old plant material is removed from the bed each spring, and that no organic material is left on the beds (which could potentially break down to humus).

Not only will these beds help to bring added color to the parking lots as they fill in, but they will also introduce new taxa to the Garden. Although these beds will be full of color in time, we will need patience in the short-term. The beds will take some time to establish, with only a few flowers this year, a bigger display next year, and with the beds hitting maturity in 2019. It is my hope that this patience will give way to something beautiful for years to come.


©2017 Chicago Botanic Garden and my.chicagobotanic.org