Plant Labeling at the Arboretum

New and Improved Plant Labeling

The Arboretum is changing every day. Terrific support from the Friends of the Arboretum, volunteers and a staff that have a “can do” attitude, keeps us moving and changing. One change that is very overdue is the addition of labels for our plants. I have worked on this on and off since 2004, but only in the past 3 years have I been able to make definite progress. This progress is due to extraordinary help from volunteers and plant experts Ken O’Dell and Sue Beamer. They have invested many hours inventorying plants, researching scientific names, researching purchasing and have created a large spreadsheet to track them all. Ken operated a nursery for many years and Sue is a certified Master Naturalist who brings project management skills from her days with Hallmark Cards. Sue’s biggest challenge is keeping Ken and me on track and conforming with the system we set up. Before their help arrived, I viewed labeling as a high priority, however, I would rather have a plant not labeled than have it misspelled or named incorrectly. Research and proof reading are very time consuming. The three of us have worked through setting standards and layouts and any other structure needed for the project to work moving forward.

A little refresher from your high school biology days.  All creatures are given scientific names consisting of a Genus species and possibly ‘cultivar’. These are written like I’ve shown – Genus is capitalized, species is not. Genus and species can be underlined or in italics. Cultivar is short for cultivated variety, and is a name given to indicate that humans manipulated the plant some way. It is capitalized and surrounded by single quote marks. Plants are also assigned a family name, which ends in -aceae. The largest families you might see represented in the gardens belong to the Rosaceae and Asteraceae – roses, of course, but also crapapples, cherries, pears, raspberries, spirea, serviceberry, quince and more. Asteraceae includes asters, daisies, black-eyed Susans, Rudbeckia, purple cone flower, coreopsis, gayfeather, sunflowers and more. It’s helpful to know what family a plant belongs to because they can often “share” pest problems. Knowing a plant is in the Rosaceae family can be enough to identify spring dieback caused by fireblight or virus diseases that attack plants in the Asteraceae family.


Hybrids are an additional category of plant name. These are the result of plants from the same genus, different species being crossed to create a new species. This is indicated if you see a plant named Genus x species. A hybridizer might see a plant with lovely red flowers and another with high drought tolerance. They take pollen from one and pollinate the other and see what comes up. Or they may see a plant with yellow variegated leaves and one with pink variegation, cross them to see if they can produce a plant with yellow and pink variegation. Cross pollinating back and forth often results in fuzzy parentage so the species may not be listed, as in Magnolia x ‘Cotton Candy’. Lots of rhododendron, roses, iris, and daylilies fall in this category. 

Verifying the correct and accepted scientific name has always been a challenge because taxonomists are constantly reevaluating identification characteristics and moving plants around to better suit the description. Add in the recent trend of providing a Latin name and a marketing name, and the task gets even more difficult. The marketing names allow the nurseries to create beautiful tags and beautiful language to attract buyers. Some examples you may see are Hydrangea paniculata ‘Bulk’ (see how I used italics instead of underline), which is marketed as Quick Fire Hydrangea and Hamamelis vernalis ‘KLMGG’, which is the accepted name for Autumn Joy Witchhazel. 

Ken has unearthed a few surprises – maples have always been in the Aceraceae family, well not always but for a very long time. However, when taxonomists revisited the family characteristics, they determined they are not really different from the soapberry family, Sapindaceae. Because Sapindaceae was described first, a very long time ago, all maples revert back to Sapindaceae. The result, Aceraceae is no longer accepted. We’ve also learned that hostas, formerly in the Liliaceae family, now have their own – Hostaceae. Another change, Verbena canadensis, a lovely little roadside plant and perennial garden favorite, aka Rose moss or Moss rose, now has the less attractive name of Glandularia canadensis. Same plant, new name. 

Our labels include the following information – Family, genus, species, cultivar, origin and may have an 8 or 9 digit number. This number provides us some quick information, but also directs us to our spreadsheet where more information can be found. Typically, the first 4 numbers are the year planted, if known. The last 4 or 5 numbers are simply for tracking. For instance, the Autumn Joy Witchhazel from above, carries the number 2014-0084.

In addition to the planted gardens, we also have the wooded area with the majority of trees planted by nature. These are being labeled as WILD-####. We chose not to use the word Native, because many of these plants are not native, just adapted to our growing conditions and easily self-seed. The majority of these labels are found along the four mulch trails. Our strategy was to label a young, medium and older specimen of each of these species on each trail. Ken and fellow volunteer, Jim Earnest, have structured a couple of tree walks along the trails, utilizing the new labeling system. Along the trails, you’ll also see small labels with the same WILD format. These are not misplaced, but the plants in that location are wildflowers that normally die back in the summer. Next spring the label may be moved by our wildflower experts to a more thriving location, in preparation for Wildflower Walks. 

There are some gardens that hold collections or themes and more information is included on the label. In the Erickson Water Garden, built for butterflies, each label notes whether it is a host or nectar plant, or both, or neither. The Xeriscape Garden has labels that indicate how much water that plant requires, based on one, two or three water drops. Notice, there are no -0- water drops – they all need water, just some more than others. Research continues for plant labeling in the herb garden. Herb garden labels will have symbols indicating whether the herb is used for cooking, medicinal, aromatherapy and/or dye.

There are nearly 600 new labels in place. Hope you enjoy learning from them as much as Sue, Ken and I have enjoyed getting them into place.

Karen Kerkhoff
Supervisor, Overland Park Arboretum & Botanical Gardens