
Wood poppy (Stylophorum diphyllum).

Flame azalea (Rhododendron calendulaceum).

Swamp milkweed (Asclepias incarnata).
Knowing Native Plants
Learn all about how and why to foster native plants in your landscape
Per Class: $30 in-person with guided walk; $25 virtual only
The Knowing Native Plants series is an annual seasonal deep dive into the native plants of the region featuring 14 Saturday classes throughout the year. Unique plant communities highlight and inform us about the landscape as their biology dictates where, when and how they grow. Unlike our Winter Lecture and Thursday Night Nature series, Knowing Native Plants contains the same programs each year. They are required attendance for our Native Plant Advocate Program.
Knowing Native Plants is a hybrid series where each class features both digital and in-person options. The in-person option includes a guided naturalist walk after the lecture.
The Preserve is well known for the beauty along the Parry Trail as the spring greets us Virginia bluebells (Mertensia virginiana), trillium (Trillium sp.), wood poppy (Stylophorum diphyllum) and, our icon, the twinleaf (Jeffersonia diphylla). As the cold and snows of winter fade, we greet these "Spring Ephemeral" visitors and explore their remarkable biology and life history. Moving to the pre-summer months, our azaleas come into their own, sparking the inquisitive eye of plant enthusiasts and participants in "Flowering Shrubs." Summer brings the action from the forest to the field as the vibrant meadow colors stand against the green backdrop of the growing season. We explore the "Meadow Magic" and the pollinators that rely on these plants as a nursery for the next generation. As summer wraps up, we explore the true stars of the meadow, those "Classic Asters" and the "Confusing Yellow Composites," in two separate classes. The colors in fall return us to the "Trees of the Preserve." We learn how and why this seasonal change occurs and what these native plants are doing the rest of the year. Winter dormancy allows us a reprieve to hone our "Plant ID" skills and learn why "Wildflowers in Winter" still serve a crucial ecological role.
Explore this year's class dates below.
2025 Classes
Jan. 18 - Wildflowers in Winter with Mary Anne Borge

Even in winter, native plants can be seen all around us. Learn how to identify the standing winter skeletons of some common native plants, what characteristics to look for and the common types of fruit you might see in winter. We will also discuss the many benefits native plants offer to both wildlife and your own gardens during the winter months. Some plants even take special advantage of the winter months to photosynthesize. Join us to find out how they do it.
Feb. 1 - Plant ID with Ed Lignowski, Ph.D.
Have you ever wondered how botanists classify plants? What characteristics make up the commonality of each group? This program will introduce you to the basics of identifying conifers and flowering plants using dichotomous keys. Learn about the vegetative and reproductive morphological features and terminology needed to use a typical plant identification key.
March 1 - Trees in Winter with Ed Lignowski, Ph.D.
Although this time of year the trees are dormant, they exhibit many interesting botanical features. Learn how to identify native deciduous trees and shrubs using buds, twigs, fruit, bark and shape as your only clues. Discover what these trees are doing to prepare for spring and how flowing sap is used to make maple syrup.
March 22 - Signs of Spring with Mary Anne Borge

One of the most exciting sights to behold is your first flower of the spring season. Meet the early flowering plants—including snow trillium (Trillium nivale), skunk cabbage (Symplocarpus foetidus) and hepatica (Hepatica spp.)—and learn how they have adapted to this potentially harsh time of year. We will attempt to identify spring-blooming species from shoots just beginning to poke through the soil.
April 5 - Spring Ephemerals with Mary Anne Borge

Spring wildflowers such as Dutchman’s breeches (Dicentra cucullaria), bloodroot (Sanguinaria canadensis), Virginia bluebells (Mertensia virginica), spring beauty (Claytonia virginica), twinleaf (Jeffersonia diphylla) and several species of trillium (Trillium spp.) color the forest floor for a fleeting moment this time of year. Learn why these wildflowers are called spring ephemerals, their life cycles and the animals that disperse their seeds and help with pollination. You’ll also learn about companion plants blooming at this same time of year.
May 3 - Late Spring Lovelies with Mary Anne Borge
A lot happens at Bowman’s Hill Wildflower Preserve between the burst of spring ephemerals and the peak of flowering shrubs. Learn about the wildlife and landscape value of the later-blooming spring wildflowers, including woodland phlox (Phlox divaricata), eastern columbine (Aquilegia canadensis), Solomon’s seal (Polygonatum biflorum), shooting star (Dodecatheon meadia), wood geranium (Geranium maculatum) and the beautiful yellow lady’s-slipper (Cypripedium parviflorum) orchid.
May 17 - Flowering Shrubs with Mary Anne Borge

The Mid-Atlantic region has a stunning display of spring flowering native shrubs that fill the Preserve and surrounding natural areas with color and fragrance every year. Learn about our native shrubs, their wildlife value and landscape beauty.
June 7 - Focus on Ferns with Ed Lignowski, Ph.D.
There are some native plants, such as ferns, that don’t flower at all. In this popular program, learn to identify many native ferns. We will highlight their evolutionary history and unusual reproductive habits, as well as their natural habitats and usefulness in native plant gardens.
June 21 - Invasive Species ID and Management with Mary Anne Borge

What is an invasive plant? What problems do invasive plants cause? Learn the answers to these questions, as well as how to identify the most common and troublesome invasive plant species in the Delaware Valley region. You’ll also learn about several alternatives for control of these exotic intruders, many without the use of chemicals.
July 26 - Meadow Magic with Mary Anne Borge

Discover the Preserve’s 4-acre meadow. This program will introduce you to native plants that thrive in a meadow habitat, including wildflowers, grasses, sedges and rushes. Learn what defines a meadow, the benefits it provides, meadow successional stages, the actions necessary to maintain a meadow and the animals that depend on this type of ecosystem. Find out why it is important to plant native species and avoid non-native ornamentals that may escape from cultivation. Whether you are looking for ideas for your own meadow or want help identifying plants in the meadows where you hike, this program is for you.
Aug. 23 - Confusing Yellow Composites with Mary Anne Borge
Join us as we focus on the confusing late summer and fall-blooming yellow composites, including goldenrods (Solidago spp.), sunflowers, coneflowers (Echinacea spp.) and beggar-ticks (Bidens spp.). She will cover the features that make aster family members unique, as well as the relationships these plants have with the insects, birds and other animals that depend on them. Find out which of these species might be good candidates for your own garden.
Sept. 20 - Classic Asters and Their Colorful Companions with Mary Anne Borge
Find out what makes aster family members different from all other plants and their importance to both wildlife and people. You’ll learn about classic asters such as New England aster (Symphyotrichum novae-angliae), aromatic aster (Symphyotrichum oblongifolium) and many other species found in different habitats; some that bloom into November; as well as bonesets (Eupatorium perfoliatum), white snakeroot (Ageratina altissima) and mistflower (Conoclinium coelestinum). Learn which of these species might be good candidates for your own garden.
Oct. 4 - Trees of The Preserve with Ed Lignowski, Ph.D.
Learn about our native trees that dominate the landscape of forests, homes and municipalities. Join a discussion of Pennsylvania’s forests, tree growth and development and how to identify the many native tree species of the Preserve. The biological and environmental changes occurring in autumn that provide brilliant seasonal tree colors will be explained.
Nov. 1 - From Flowers to Seeds with Ed Lignowski, Ph.D.

How do angiosperms reproduce sexually? Learn about the life cycle of flowering plants, from pollination to fruit and seed dispersal. The general anatomy of flowers will be covered along with specific examples of native plants that illustrate the many interesting differences in floral structure and function occurring in nature.