Alan Branhagen

Alan Branhagen is Director of Operations at the Minnesota Landscape Arboretum, and previously held the position of Director of Horticulture at Powell Gardens, Kansas City's botanical garden. He is the author of The Gardener's Butterfly Book and has written articles for publications including Fine Gardening, Missouri Gardener, Missouri Prairie Journal, Landscape Maintenance, and Restoration and Management Notes. Alan is a naturalist and plantsman specializing in botany, butterflies, and birds, utilizing his background in garden design and management. He is currently creating and restoring a three-acre prairie and woodland garden around his home.

Author of 
Native Plants of the Midwest: A Comprehensive Guide to the Best 500 Species for the Garden

The Gardener's Butterfly Book

James B. Calkins, Ph.D.

Jim CalkinsJim is a landscape horticulturist with extensive experience in plant identification, culture, and use. He is an expert on the selection of landscape plants and strongly supports the notion that there are no bad plants - only good plants planted in the wrong place. As an outdoors enthusiast, Jim has a special interest in native plants and plant communities and his experiences have given him a unique, big-picture perspective when it comes to plant growth requirements and the use of plants in designed landscapes.

A member of the Department of Horticultural Science at the University of Minnesota for nearly thirty years, Jim has extensive teaching and research experience on just about any topic related to horticulture including plant propagation, nursery field and container production, woody and herbaceous plant identification and use, and landscape design, implementation, and management.

Jim is a Certified Nursery and Landscape Professional and has been an active member of the Minnesota Nursery & Landscape Association (MNLA) for over 30 years. In addition to working as a horticultural consultant and landscape designer, he currently serves as the Research Information Director and the Regulatory Affairs Manager for the MNLA and speaks extensively on topics related to horticulture including for the Minnesota State Horticultural Society and the
Minnesota Landscape Arboretum where he has taught classes for more than 20 years.

Jim also has a strong interest in ecosystem and watershed management, including the impacts of designed landscapes on stormwater runoff and water quality and how residential and commercial landscapes can be designed to be both functional and environmentally sound. In this regard, he served on the Minnehaha Creek Watershed District Board of Managers for 18 years and as board president for nine years.

Jim also serves on the Minnesota Noxious Weed Advisory Committee, the Minnesota Invasive Species Advisory Council, the advisory board for the Minnesota Invasive Terrestrial Plants and Pests Center, and the Governor's Committee on Pollinator Protection. He has been described as a Ph.D. with a sense of humor.

Alex Eilts

Alex EiltsAlex received his doctorate in ecology and evolutionary biology from the University of Arizona. He loves plants, and currently helps maintain the University of Minnesota plant diversity collection which contains over 1,600 species, spread across 200 plant families. He is also a professional science communicator, whether making videos of his own ( or playing other's videos as the festival coordinator for the Northstar Science Film Festival (

Beth Markhart

Beth MarkhartBeth holds a B.A. in plant ecology from the University of Colorado and an M.S. in plant physiology from the University of MN. She has served as a board member of the Society of Wetland Scientists and the MN Native Plant Society, instructed biology and ecology, and spoken to many professional and interest groups since 1980. As Trustee of the Markhart Organics Endowment Fund at the UMN, Beth enjoys interacting with undergraduates who enthusiastically aspire to better the world through ecologically based farming systems.

Beth is employed by Prairie Restorations, Inc., the 42-year old restoration company and producer of Minnesota native seeds and plants. The website for Prairie Restorations:

Christy Marsden

Christy MarsdenMaster Gardener Extension Educator and Education Manager

Christy Marsden is a member of the State Leadership Team with the U of M Extension Master Gardener Volunteer Program. As the Education Manager, Christy oversees Master Gardener Volunteer training and education statewide through the Core Course, volunteer toolkits, and other outreach methods. Christy also works with the Arboretum Education team to build adult education programs online and in conjunction with the Master Gardener Volunteer program.

Before working with the Landscape Arboretum, Christy was a county-based Horticulture Educator with the University of Wisconsin Extension in Rock County. Christy has a BS in Human Development and MS in Horticulture and Agronomy from the University of California, Davis. As a native of California she's learned to love the seasons, especially amongst the trees.

John & Jenny Thull

John and Jenny manage over 10 acres of research vineyards for the Grape Breeding Program at the University of Minnesota's Horticultural Research Center (HRC) which is overseen by Dr. Matthew Clark. The vineyards contain approximately 10,000 novel seedling vines of all ages. These vines are continually evaluated for cold hardiness, disease tolerance, growth habit productivity, and fruit quality for wine production and fresh eating. Every year new vines are being planted into the research plots. Growing so many different vines is quite challenging and extremely interesting which gives John and Jenny a whole new appreciation for wine tasting.

While working over the past 10 years at the HRC and in their own 2 acre vineyard, John and Jenny have shared their experience with many growers through talks, presentations, and in-field clinics not only in Minnesota but also in many other regions that grow cold hardy vines.

Aside from grapes, John and Jenny have grown well over 300 different varieties of pumpkins, squash, and gourds which get displayed every year at the Minnesota Landscape Arboretum and are sold through the Apple House at the HRC. Stop on out in the Fall to enjoy the fruits of their labor!

Laura Vogel

Laura Vogel

Arboretum Adult Education Programs Manager
As Adult Education Programs Manager, Laura connects adults to their natural world, and strives to connect public horticulture to issues of environmental, food, and social justice. This is achieved through programs, workshops, walks, and summits in gardening, photography, culinary topics and more.

Laura started her path in horticulture with 4-H and landscaping her parents' backyard. She has a B.S. in Public Horticulture from Purdue University and an M.S. in Public Horticulture Management from the University of Delaware and Longwood Gardens.

Professionally, Laura has been part of the education staff at Missouri Botanical Garden, Longwood Gardens, and Brookside Gardens.

In her free time, Laura tries to keep up with twin toddlers and squeezes in vegetable gardening and cooking on the side.

Julie Weisenhorn

Minnesota native Julie Weisenhorn holds master's degrees in visual communication and horticulture from the University of Minnesota where she taught landscape design and served as state director of the Extension Master Gardener Program. As an Extension horticulturist, Weisenhorn has statewide responsibility for horticulture teaching, research and outreach with special focus on plant selection and sustainable residential landscape design. She is continuing the 4th year of the Flowers for Pollinators ( ) study on annual flowers and has added a second study called Pollinators for food
studying annuals flowers and pollination of bell peppers. Weisenhorn coordinates and regularly appears on the popular WCCO Radio Smart Gardens show (Saturdays, 8-9am, AM 830), and released the second version of the Plant Elements of Design plant selection database (

In her own words, "This is the best job I have ever had."