by Lissa Lutz, NC State Extension Master GardenerSM volunteer of Durham County
Local Ecotypes and Keystone Genera. What are they and why do they matter? Where can I get them? The second question is easy to answer: Come to the Durham Master Gardener Plant Sale on April 11, 2026. Lissa Lutz, chair of the plant sale committee answers the first question.
Keystone Plants
Keystone plants are a sub category of native plants that are uniquely essential to the local food web. According to research by entomologist Dr. Doug Tallamy1, a small fraction of native plants (about 14%) support the vast majority (90%) of butterfly and moth species. Without these specific plants, many caterpillars cannot survive. This leads to a collapse in bird populations that rely on them for food. Without keystone plants, the ecosystem collapses because the food supply and habitat for pollinators is threatened. Three example of perennials that are considered to be Keystone plants in our region are: Goldenrod (Solidago); Sunflower (Helianthus) and Asters(Symphyotrichum).
Goldenrod (Solidago)
We will have several varieties of Solidagos at the plant sale: Solidago caesia; Solidago bicolor; Solidago erecta; and Solidago rugosa ‘Fireworks‘. Goldenrods are considered a keystone plant species in that they support numerous species of birds, butterflies, bees and other insects. Goldenrods tend to be deer resistant, and contrary to popular belief they do not cause hay fever. Of special interest is Solidago caesia. It, is unusual in that unlike most other goldenrods it is happiest in a woodland setting. Rarely growing taller than 2 feet, it spreads slowly and politely, offering showy yellow blooms along bluish stems from late summer through fall. Blue Stemmed Goldenrods in the sale were grown from seeds collected from plants growing along New Hope Creek in Orange County, making this plant a local ecotype (more about what that means in the next section).
Solidago caesia supports Wavy-lined Emerald (Synchlora aerata) larvae. Flowers are attractive to butterflies, bees, and other pollinators. Songbirds eat the seeds. (Image credit: Dan Mullen CC BY-NC-ND 4.0; Debbie Roos)
Sunflower (Helianthus)
The main attraction in the Heilianthus family will be Helianthus angustifolius (Swamp sunflower). This is a great plant for the back border of a pollinator garden. Why the back border? Because it often grows to 8 feet tall. It may need to be staked in late summer if it is planted in a windy area but it will give you cheerful daisy like blooms well into the fall.
It is visited by specialized bees as well as generalist bees (such as bumblebees and honey bees). It is a source of nectar for many butterflies during fall migration and serves as the larval host for the Silvery Checkerspot butterfly.
Helianthus angustifolius (Swamp sunflower) has multiple blooms that sway in the breeze and it attract a number of pollinators. It is also a favorite of song birds. (Image credit: J. Biochemistn CC BY-NC 2.0)
Asters(Symphyotrichum)
Do we have a variety of Asters for you! Symphyotrichum georgianum (Georgia Aster); Symphyotrichum laeve (Smooth Blue Aster); Symphyotrichum oblongifolium (Aromatic Aster); Symphyotrichum patens (Clasping or Late Aster) will all be there ready to go home with you. The flowers have a long bloom season lasting from late summer until the first frost. Native bees nest in the dead, hollow stems, so gardeners are encouraged to cut back dead stems to 12 to 24 inches and allow them to remain standing until they disintegrate. Read more about best practices for stem-nesting bees in this NC Extension publication.
Asters are a diverse group of plants. Some like sun others like a bit of shade. The are a must in the pollinator garden providing nectar in the fall and a home in the winter. (Image credit: Andrea Laine CC BY-NC-40; Debbie Roos)
Local Ecotypes
Local ecotypes are native plants that have been grown under local conditions. Using locally sourced plants increases survival rates, promotes genetic diversity, and supports specialized local pollinators and wildlife. They are crucial for restoring, sustaining, and improving local biodiversity. In addition to the Blue Stemmed Goldenrod mentioned earlier there will be many other plants that are local ecotypes.
Chrysopsis mariana, or Maryland Golden aster, is an under-utilized, tough as nails native that has bright yellow daisy-like blooms on 1 to 2 foot plants in the fall. This 2018 NC Botanical Gardens Wildflower of the Year attracts bees, butterflies and other pollinators, and thrives in poor, sandy, well-drained soils, though it is quite adaptable. The plants can be short lived but will reseed readily. They are also deer resistant. Maryland Golden asters in the sale were grown from seeds collected from plants growing on a roadside in Orange County.
Penstemon laevigatus, or Eastern Smooth Beardtongue, is a lovely Piedmont native that is easy to grow in sun or part shade and a variety of soils. The evergreen basal rosettes produce 2 to 3 foot stems with pale purple blooms from May through July. Hummingbirds, bees and other pollinators visit the tubular flowers. Eastern Smooth Beardtongue is an excellent cut flower and is moderately deer resistant. Plants in the sale were grown from seeds collected from plants growing along a power line in Orange County.
Chrysopsis mariana, or Maryland Golden aster (l) and Penstemon laevigatus or Eastern Smooth Beardtongue (r) will be available for sale. They are both sourced from locally grown seeds which helps them to live a healthy life in your garden. (Image credit: Cathy DeWitt CC-BY-NC-ND 4.0; JC Raulston Aboretum, CC BY, 2.0)
Other Powerhouse Pollinator Plants that will be available include: Eupatorium (serotinum, hyssopifolium), Rudbeckia (triloba, fulgida); Amorpha fruticosa, Oenothera fruticosa, Parthenium integrifolium, Cunila origanoides, Rhexia virginica, and Lonicera sempervirens. According to National Wildlife Federation each of these species support 15 or more insect species.
This is only a partial list of the plants that will be available. We have an excellent collection of vegetables (tomatoes, peppers, eggplant, cucumbers,and lettuce) including many small varieties that can be easily grown by people living in apartments or houses with limited space. Herbs are a great way to spice up your kitchen and we will have several varieties of basil, ginger, rosemary and chives. There will also be several well-behaved non native plants and a selection of shrubs and trees grown by our exceptional propagation committee. You can find a full list of plants at: https://www.backyardtreasuresplantsale.org/.
While you visit the sale, don’t forget to stroll through our Durham County Extension Demonstration Garden and see many of the plants that are being sold. A previous blog post describes the recent changes and additions to the demo garden.
Notes: 1 Doug Tallamy is an entomologist, conservationist, and professor at the University of Delaware. His work has informed our understanding of the relationship between native plants and wildlife. He has written several books and these are available at his website: https://homegrownnationalpark.org/doug-tallamy/
Additional Reading and Resources
The National Wildlife Federation has developed a list of Keystone Plants by ecoregion: https://www.nwf.org/Native-Plant-Habitats/Plant-Native/Why-Native/Keystone-Plants-by-Ecoregion
The NC Wildlife Foundation has a list of perennials and annuals that are great pollinator plants for our state: https://ncwf.org/habitat/native-pollinator-plants/perennial-annual-flowers/#:~:text=Great%20Blue%20Lobelia,seed%20in%20ideal%20garden%20conditions.
The NC Audubon Society offers a variety of strategies for increasing the number and diversity of birds in our state: https://www.audubon.org/north-carolina.
If you are interested in having your garden certified as a wildlife certified habitat go tohttps://ncwf.org/our-work/garden-for-wildlife/certified-wildlife-habitat/
Shortlink: https://wp.me/p2nIr1-7j9
