Extension Master Gardener Volunteers of Durham County

By Jeanne Arnts, NC State Extension Master Gardener^SM volunteer of Durham County

*Considered one of the most important species of pollinator bees in North America, the common eastern bumblebee, (Bombus impatiens) on Bee Balm, (Monarda didyma ‘Lombada’),*
Image credit: Marcia Kirinus

In my December 2024 blog, “From Beloved to Invasive: How Does it Happen?”, I concluded by stating that I would follow up with suggestions for native plant alternatives to invasive ornamentals. While a comprehensive guide isn’t feasible in a single post, I will highlight some of the most common and troublesome invasive plants and their native replacements.

Challenges in Replacing Invasive Plants

Replacing invasive plants with natives is not always straightforward, as there are rarely perfect native substitutes. An invasive plant may bloom longer, at different times, or offer other aesthetic appeals that native alternatives do not. However, invasive plants harm local ecosystems by outcompeting native species and failing to support caterpillars and specialist pollinators. While adult butterflies can seek nectar from any plant, their caterpillars depend on the leaves of their host plants, with which they have evolved over millennia, for survival. Research by Tallamy, et al., indicates that a biomass of at least 70% native plants is required in a nesting area to support bird nestlings that rely on caterpillars for nutrition. In my yard, I prioritize adding species that support native specialist bees and caterpillars.

*This Pine Warbler snacked on this juicy caterpillar and proceeded to hunt for more.* (Image credit: Ryan Sanderson)

Native Trees and Shrubs to Replace Invasive Ornamentals

Bradford Pear (Pyrus calleryana ‘Bradford’) → Serviceberry (Amelachier arborea), Dogwood (Cornus florida), Redbud (Cercis canadensis), or Fringe tree (Chionanthus virginicus)
- Though the Bradford pear was initially thought to be a sterile hybrid when introduced to the U.S. nursery trade in 1964, its cultivars can cross-pollinate and revert back to the invasive Callery pear species. Like most invasive shrubs and trees, birds eat the fruit and spread the seeds through defecation, leading to aggressive spread of this species. Dogwood and Redbud are excellent alternatives, supporting multiple caterpillar species (101 for Dogwood and 25 for Redbud). If you have a Bradford Pear consider replacing it with Serviceberry, Fringe Tree, Redbud or Dogwood.

Butterfly Bush (Buddleja davidii) → Buttonbush (Cephalanthus occidentalis), Sweet pepperbush (Clethra alnifolia), Virginia sweetspire (Itea virginica)
- While Butterfly Bush attracts many butterflies, it doesn’t support their caterpillars. Buttonbush, on the other hand, supports native bees, as well as moths, such as the buttonbush clearwing moth (Hemaris diffinis). Sweet pepperbush is also a great alternative, supporting native bees and butterflies, as well as night-flying moths. Virginia Sweetspire thrives in part shade and moist soil, and like the other alternatives, serves as a host plant for various caterpillars.

Heavenly Bamboo (Nandina domestica) → Yaupon Holly (Ilex vomitoria) or Inkberry (Ilex glabra)
- Nandina is popular for its red berries, but they are toxic to birds and mammals. Yaupon Holly and Inkberry provide similar ornamental value, non-toxic berries, and ecological benefits. They are nectar-rich and host plants for 44 species of caterpillars. Both are dioecious, meaning male and female plants are needed to produce berries.

Burning Bush (Euonymus alatus) → Strawberry Bush (Euonymus americanus) or Fragrant Sumac (Rhus aromatica)
- Burning Bush is prized for its red fall foliage but is invasive. Strawberry Bush, also known as Hearts A’Busting, offers similar aesthetics but needs protection from deer. Fragrant Sumac also provides vibrant fall color and summer fruit for wildlife.

*Serviceberry, (Amelanchier arborea) in the spring before the leaves come out.*
Image credit: NCSU Plant Toolbox peverdonk CC BY-NC 2.0)

Native Vines to Replace Invasive Vines

Chinese & Japanese Wisteria (Wisteria sinensis, W. floribunda) → American Wisteria (Wisteria frutescens)
- Unlike its invasive counterparts, American Wisteria is less aggressive and can be managed with pruning. Like it’s invasive cousins, it needs support of a trellis or wall.

Japanese Honeysuckle (Lonicera japonica) → Crossvine (Bignonia capreolata) or Coral Honeysuckle (Lonicera sempervirens)
- While Japanese Honeysuckle attracts generalist pollinators, it doesn’t support specialized relationships with local insects. Its invasive nature also harms native plants. Crossvine, a native alternative, supports a wide range of caterpillars and pollinators, including hummingbirds and bees. I particularly like Crossvine because of its abundant blooms, I planted one near a pine that receives sun, and it climbed the pine up to a height of 50 feet without girdling it. Crossvine’s claim to fame, according to N.C. State, is that it produces more blooms per square foot than any other vine. Honeysuckle, a bit tamer, also attracts hummingbirds and bees and supports nectar-feeding butterflies.

From left to right: Crossvine, (Bignonia capreolata) climbing up a pine tree. Image Credit: Susan Strine CC BY 2.0. Coral Honeysuckle, (Lonicera sempervirens) & White-lined sphinx Moth, (Hyles lineata) Image Credit: Ronnie Pitman. CC BY-NC 2.0 Coral Honeysuckle, (Lonicera sempervirens) in flower Image Credit: Chris Kreussling CC BY-NC-ND 2.0

Native Ground Covers to Replace Invasive Ground Covers

English Ivy (Hedera helix) → Native Violets (Viola canadensis, V. sororia) or Wild Strawberry (Fragaria virginiana)
- English Ivy is an invasive ground cover that harms trees and structures. Native violets and Wild Strawberry are better alternatives, offering ecological benefits like providing berries for wildlife. Be aware that there is an invasive, exotic wild strawberry plant look alike called, ‘Mock strawberry’, (Potentilla indicia), that does not provide any ecological value. You can identify it in the early spring because it has yellow flowers. The native wild strawberry has white flowers.

Periwinkle (Vinca minor, V. major) → Green and Gold (Chrysogonum virginianum) or Golden Ragwort (Packera aurea)
- Both Green and Gold and Golden Ragwort provide vibrant yellow spring flowers, with ecological benefits, including supporting pollinators. They both bloom yellow in the spring.

Monkey Grass (Liriope muscari) → Blue-eyed Grass (Sisyrinchium angustifolium)
- While Liriope is a “lesser threat” invasive, Blue-eyed Grass is a more attractive alternative, although it prefers less shade. For deep shade, consider Chrysogonum virginianum.

From left to right, Native Violet, (Viola canadensis), Image Credit: ScottCC BY 2.0 . Green and Gold, (Chrysogonum virginianum), Image Credit: Marcia Kirinus. Blue eyed grass, (Sisyrinchium angustifolium), Image Credit: Debbie Roos

Choosing Native Cultivars (‘Nativars’) Wisely

In many plant nurseries, you will find cultivars of native plants. These plants have been bred to highlight certain attributes. Many ecologists prefer to use straight species to promote diversity, but not all cultivars are harmful. Research from Penn State University indicates that 50% of cultivars are equally or more effective at attracting pollinators than their straight counterparts.

What should you avoid?
Avoid cultivars with double flowers, as these often replace the reproductive parts necessary for pollinators. Also, avoid cultivars with unusual leaf colors (e.g., purple or variegated) as they may have different chemical compositions that make them less suitable for caterpillars.

What attributes are okay?

Changes in size (e.g., dwarf varieties) or growth habits typically don’t affect the plant’s ecological role.
Cultivars bred to produce more flowers can benefit pollinators, provided the flowers still offer nectar and pollen.
Increased hardiness to extreme weather conditions can help native cultivars survive and benefit wildlife.

Research Before You Buy

Before purchasing new plants, I always consult the NC State Plant Toolbox for reliable information on growth conditions and ecological value. I also avoid purchasing insecticide-treated plants, as they can harm pollinators and beneficial insects. Buying from reputable native plant nurseries or Master Gardener plant sales ensures that you make safe, beneficial choices. The next Master Gardener plant sale will be on April 5, 2025. Learn more here.

By making thoughtful plant selections, we can create beautiful landscapes that support local ecosystems. Every native plant added to your yard makes a difference!

Resources and Additional Information

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By Peter Gilmer, NC State Extension Master Gardener^SM volunteer of Durham County

(Image credit: University of New Hampshire Extension)

The “dead of winter” is an expression understandable when we had two weeks of cold and a touch of snow, not so understandable with temperatures in the 70s. For plants, the winter is a time of dormancy, both for deciduous as well as evergreen shrubs and trees. This time of year for gardeners often means planning, ordering seeds, and waiting for the soil to warm. It is also the right season for hardwood cuttings, a simple but often forgotten plant propagation technique.

Hardwood cuttings (also known as scions) are taken during the dormant stage of a woody plant, including both trees and shrubs, usually involving last year’s growth, and can be considered from the first hard freeze (late November for us?) through bud break in early spring. The technique is simple, fun, and often considered for a favorite plant or when seed propagation for a specific plant is difficult or slow.

(Left) A healthy donor plant, red twig dogwood (Cornus sericea), showing last year’s growth as the reddest of the stems, each about the diameter of a pencil. (Right) Five cuttings, ready to be dipped in planting hormone powder. Each is cut horizontally just below a bud, and at an angle just above an upper bud. (Image credit: Peter Gilmer)

Where, When, and How to Take Cuttings

To be successful, the donor plant must be healthy. The cut is made just below a bud, often near the base of the plant and should be done with the health and final appearance of the donor plant in mind. The stem should be about the diameter of a pencil, and length does not matter initially as the stems taken will be cut again before sticking. The term sticking is used to describe the simple act of pushing the cut stem into the growing media. Plants with suckers and shoots are often good candidates, and juvenile stems do better than more mature ones.

Cuttings are best taken in the early morning on a cloudy day, to minimize sun exposure, and should be placed in an opaque plastic or paper bag, with a moist cloth or paper towel around the base. A cooler (without ice) may be helpful if many cuttings are being taken. Remember, cutting a stem is an injury to the donor plant, and should be done with a sharp tool cleaned with alcohol or a bleach solution to avoid disease transmission.

Once the long stem is taken from the donor plant, that stem is cut again with attention paid to the final stem length, bud locations, and polarity. In general, final cuttings should contain at least one bud that will be below ground, and at least one above ground. The bottom cut is generally made transversely just below a bud, and the upper cut made at an angle just above a bud. Polarity is easier to maintain if the angled cut is always up, and this also keeps moisture from potentially sitting in droplet form on the top of the stem. Stems will not root if planted inverted. The cuttings at this point are generally six to ten inches long, although this depends on the arrangement of the buds. Note that no terminal buds are kept in this technique, as the stems are usually too small in diameter near the top of the stem.

Rooting and Care of Hardwood Cuttings

Some cuttings can be stuck directly into the planting media, but most authors recommend dipping the base of the cut stem into rooting hormone prior to sticking. Rooting hormone can be purchased at most big box stores, usually in a powder form, and should be handled with gloves and eye protection, as the hormone can be caustic to eyes and to skin. Never dip the cutting into the original container to avoid contamination, and don’t use too much. More is not better, and in fact can inhibit root development. The planting media required is not unique or specific. Any commercially available planting soil or seed starting mix will work. It may be important to not have fertilizer already in the media, as new roots form more easily without initial fertilizer exposure. Most media options contain two or more of the following: perlite, pumice, peat, sand, and fine bark chips.

Taking care of the cuttings is relatively easy. The media should be kept moist, but not soggy. It is essential to avoid desiccation of the new cuttings, but cuttings are more commonly injured by being too wet (for example, in soil that does not drain well). The cuttings will need protection from direct sun, temperature extremes, and animal predation. For some this may be as easy as a container on the north side of the house, perhaps with chicken-wire on the top, with the option to move the container indoors during very cold nights.

Roots can take several months to form, so patience is required. The best way to assess root development is to tip over the container, gently dumping the contents. A cutting with generous fibrous root formation will maintain the entire planting media, while minimal or no root formation will allow the media to fall away. The cuttings can be fertilized once root formation is confirmed, and hardened off by gradually increasing sun exposure as leaves begin to form.

Have fun with this technique. It is fine to experiment. If you wonder “Can I take a cutting of this plant?”, give it a try. It is quite useful to research the potential donor plant using basic cell phone techniques. Simply ask Google “What is the best way to propagate “X” plant?”. We recommend searching for research-based information on sites with the domain .edu– such as https://plants.ces.ncsu.edu. For example, the best propagation technique for red twig dogwood is a hardwood cutting, while the best technique for white oak is an acorn. Enjoy this propagation technique in the dead of winter.

Resources and Additional Information

Hartmann and Kester’s Plant Propagation: Principles and Practices, 9th Edition. Pearson, 2018.

NC State Extension Gardener Handbook online chapter on propagation, 2018. https://content.ces.ncsu.edu/extension-gardener-handbook/13-propagation

Clemson Cooperative Extension Home & Garden Information Center online fact sheet.

Hardwood Cuttings for Shrub & Tree Propagation

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