Q&A: Late Bloomers for the Garden

a red-spotted purple butterfly is feeding on nectar from a native Eupatorium plant with white flowers
Red-Spotted Purple butterfly on a native Eupatorium in September. Photo: M. Talabac

Q:  A lot of my new native plant garden beds contain species that bloom in spring and early/mid-summer. What can I add for pollinators that blooms late?

A:  Fortunately, there are numerous late-season nectar sources, though most are sun-loving species. They are very attractive to migrating Monarchs and any other butterfly on the wing in late summer and autumn, plus bees, wasps, beetles, flies, and plenty of other insects. Seed-eating birds also appreciate the food source once the seeds of those plants ripen by the end of the growing season; nature’s bird feeders.

Lots of late-flowering native plants are in the aster family, including: Ironweed (Vernonia); Goldenrods (Solidago and Euthamia); Asters (formerly genus Aster, now named Doellingeria, Eurybia, Ionactis, or Symphyotrichum); Cut-leaved Coneflower (Rudbeckia laciniata); Blazing-star (Liatris); Elephant’s-foot (Elephantopus); Beggarticks (Bidens); Wingstem (Verbesina); Helen’s Flower (Helenium); perennial Sunflowers (Helianthus); Climbing Hempvine (Mikania scandens); and the Eupatorium group (several common names and genera; Eupatorium, Eutrochium, Conoclinium, Ageratina).

Outside of the aster family, you can also consider Rosemallow (Hibiscus), Obedient Plant (Physostegia virginiana), Turtlehead (Chelone), Common Witchhazel (Hamamelis virginiana), Gentian (Gentiana), Tall Phlox (Phlox paniculata), Lobelia (Lobelia), and Flowering Spurge (Euphorbia corollata).

By Miri Talabac, Horticulturist, University of Maryland Extension Home & Garden Information Center. Miri writes the Garden Q&A for The Baltimore Sun and Washington Gardener Magazine. Read more by Miri.

Have a plant or insect question? The University of Maryland Extension has answers! Send your questions and photos to Ask ExtensionOur horticulturists are available to answer your questions online, year-round.

Azaleas and Home Gardens

Spring is incomplete without the bold and soft hues of azaleas in your home garden. These spectacular plants are prevalent and have dominated yards and countless gardens in North America. These plants originated in Asia and made their way to the US via Europe around two hundred years ago. Since then, according to the American Azalea Society (ARS), over 10,000 different cultivars, or cultivated varieties, have been registered or named. The high demand for cultivated azalea can be attributed to its small manageable dwarf sizes, diverse attractive colors, deep green leaves year-round, and adaptability to the climate, making them easy to grow.

However, there are equally beautiful native azaleas in North America that are seldom seen in home gardens and are still not as well-known as their Asian cousins. To find them, it would be best to wander from the landscaped yards into the woods. In this post, I talk about the extraordinary beauty and ecology of native azaleas, as they require more attention and care from the gardening community.

What are native azaleas?

Azaleas are members of the heaths (Ericaceae) plant family, which includes cranberry, blueberry, and huckleberries. Because there is often confusion among people between azaleas and rhododendrons, it is much easier to remember that all azaleas are rhododendrons, but that all rhododendrons are not azaleas. In fact, azaleas belong to the genus Rhododendron. Azaleas native to North America are usually medium-sized or tall shrubs with soft, deciduous leaves, funnel-shaped flower lobes, and long tubular flowers with stamens extending beyond their showy petals. There are eighteen North American native azaleas (visit the American Azalea Society and American Rhododendron Society to learn more).

Why grow native azaleas?

Native azaleas display shades of white, orange, pink, red, and yellow throughout the spring and summer. Although most people associate azaleas with spring, several native ones bloom in mid and late summer. It is often noticed that azaleas in their natural habitat show some staggering in their flowering timing, and their flowering durations usually range between 15 to 20 days. So, if you carefully select species based on their flowering timing, you can have azaleas bloom in your home gardens for at least four to five months. Unlike the evergreen cultivated ones, native azaleas have exceptional fall color before they shed their leaves for winter. Most native Azaleas can reach heights of 4’-8’ and can be used in hedgerows and as the background to other flowering dwarf shrubs. Some of the common native azaleas in the woodlands of Maryland, Virginia, and DC are smooth azalea (Rhododendron arborescens), swamp azalea (Rhododendron viscosum), pinxter azalea (Rhododendron periclymenoides), coast azalea (Rhododendron atlanticum) and early azalea (Rhododendron prinophyllum).  

Besides the colorful hues in your green space, growing azaleas will also help maintain the native pollinator network in your local environment. Native azaleas can sustain a variety of fauna through their flowers; they are attractive to bees, butterflies, moths, and hummingbirds. The quantity and quality of nectar and pollen among these plants are often observed to be higher than in the cultivated ones. In general, they have a high amount of concentrated nectar and string-like pollen threads that help attract myriad forms of floral visitors native to North America.

Some azalea species have attractive warm orange and red flowers, and birds can detect warm colors easily. At the same time, insects, including bumblebees and smaller bees (e.g., Andrena sp.), are attracted to light pink, purple, and white palettes. Certain native species, such as sweet azalea and piedmont azalea, have a strong sweet fragrance. Besides providing a sweet smell, their fragrance also helps attract night pollinators such as moths. Nectar volume among the azalea flowers is relatively low compared to its nectar concentration; therefore, the migratory ruby-throated hummingbird makes occasional visits, as birds usually prefer flowers with high voluminous nectar. Their unique floral characteristics also attract diverse butterflies, recognized as potential pollinators for these species. Commonly observed butterflies are eastern tiger swallowtails (Papilio glaucus), silver spotted skippers (Epargyreus clarus), and great spangled fritillaries (Speyeria cybele). The flapping of butterfly wings helps transfer pollen from the male to the female organ and facilitates successful reproduction in these plants. Therefore, growing different shades of native azaleas in your yards and home gardens will be a good idea to support native pollinators.

Native azaleas are also relatively free of pests and diseases compared to cultivars, making them low-maintenance plants. They do not require regular pruning and are moderately slow growers. However, knowing the ecology of these species may be helpful for plant growers. For example, in the forest, these plants are mostly found as an understory of other tall hardwood trees like oaks and chestnuts; therefore, they will do well in less light and shaded areas in the home gardens. Most of them require moisture with good drainage and humus-rich acidic soil. You can learn more about the detailed requirements of the conditions preferred by these plants at the American Azalea Society.

It is never too late to add these cool plants to your home garden.

By Shweta Basnett, Fulbright Postdoctoral Fellow, Department of Entomology, University of Maryland. Visit her website for more information about her current research.


Native Plants Add Beauty and Support Wildlife 

wild bergamot flowers are lavender color
Native wild bergamot (Monarda fistulosa) attracts pollinators from butterflies to hummingbird moths and is both deer and rabbit-proof. Photo: Elmer Verhasselt, Bugwood.org

I love native plants. I garden for beauty and wildlife and nothing supports healthy habitats better than native plants. 

So what are native plants? They are beautiful, resilient plants that naturally occur in an area.

Having evolved over millennia with native wildlife, they naturally support them best. A native white oak supports 557 species of butterflies and moths while a non-native gingko tree supports just five.  

So if you want to support bees, butterflies, and beneficial insects that help control pests, native plants are the way to go. 

They also support larger wildlife such as birds with their seeds, fruit, shelter, and places to raise young. Again, native plants evolved with them, so they naturally provide what they need.  

According to conservationist, author, and entomologist Doug Tallamy who penned the bestsellers “Bringing Nature Home” and “Nature’s Best Hope,” native plants support 29 times more wildlife diversity than non-native plants.  

Well adapted to our soil and climate, native plants are resilient with a capital “R.” They’ve persisted through many hot, dry, wet, and cold years, surviving all previous climate change that has occurred, positioning them well to adapt to future changes. 

Adapting over eons makes you tough. Native plants have fewer pest and disease issues and some have deep roots which make them drought resistant. That means less watering, fewer chemicals, and a healthier landscape. 

Did I mention how beautiful they are? There is a nasty rumor out there that native plants are weedy. Bosh and balderdash.   

Native coral honeysuckle trumpets red/yellow/orange flowers that welcome hummingbirds. Threadleaf coreopsis wafts a riot of petite yellow daisies in a drift of lacy foliage.  

Wild blue indigo sports 4-foot stems of deep blue sweet-pea-like blooms. Cardinal flower flashes brilliant red and is a magnet for hummingbirds and butterflies.  

Bees love to rummage among the pure white blossoms of native foxglove. And goldenrods carousing with purple asters are the very definition of fall beauty.

Don’t get me started on native trees and shrubs. I love ninebark’s white pompoms, the red dangling fruit of chokeberry, the deep maroon flowers of Carolina allspice (native from our South), skinny willow oak leaves, and the giant leaves of pawpaws

red flower of Carolina allspice
Carolina allspice (Calycanthus floridus). Photo: Miri Talabac

How can you find out what native plants might work in your landscape?  

Discover many resources – including recommended native plants for Maryland on our website and on the Maryland Native Plant Society website.

My favorite native plant reference, “Native Plants for Wildlife Habitat and Conservation Landscaping,” has color photos and plant profiles. Download it for free.

Where do you find native plants? Visit your favorite garden center. Native plants are becoming more common. If they’re not there, ask. Nurseries grow and buy based on client interest.  

The Maryland Native Plant Society website also lists native plant sales and nurseries on their website.

Many Master Gardener groups – including ours – hold spring plant sales that include native plants. Contact your county/city coordinator to learn if one is scheduled near you.

I hope I’ve encouraged you to include some native plants in your landscape to add beauty, invite wildlife and support a healthy ecosystem.  

By Annette Cormany, Principal Agent Associate and Master Gardener Coordinator, Washington County, University of Maryland Extension. This article was previously published by Herald-Mail Media. Read more by Annette.

Lawn alternatives for shady yards

Although a non-native example, this New Zealand Hair Sedge (Carex comans) illustrates the soft, flowing look multiple sedge species provide. Photo: M. Talabac

Q: I’m happy to try a lawn alternative for my shadier areas but I’d like it to look more like a lawn than a groundcover or mix of flowering plants. What kind of grasses work for that?

A:  Not many true grasses will grow well if you have less than full sun, but several perennials that look like grasses can work nicely. My primary recommendation would be to try one or more species of sedge (Carex). I was excited to see the study results for sedges from Mt. Cuba released recently: “Carex for the Mid-Atlantic Region” that may be a useful reference.

Mt. Cuba Center is a public garden and research facility in Delaware which displays and studies native plants, and they perform periodic plant trials to evaluate species and cultivars for garden performance. Lately they have been including an assessment of pollinator appeal as well, though in this particular case that wouldn’t apply since sedges are not grown for pollinator draw. (Even though the caterpillars of several of our less-often-seen butterflies feed on sedges.)

Sedges are a species-diverse group and make for an excellent grass-like aesthetic in partial shade to full shade. Many form low soft-looking tuffets, though with time or dense planting can form a more-or-less uniform “lawn.” Still, don’t expose them to much foot traffic since nothing is quite as tolerant to that as turfgrass. Well over one hundred sedges are native in Maryland, and the Mt. Cuba study results include lists of those well-suited to more sun than shade, more shade than sun, and a tolerance to mowing (not that they require it by any means).

A few true native grass species tolerate some shade, but won’t give you a comparable look to a lawn since they grow much taller or have a different leaf color or texture (often wider, coarser leaves). Examples include river oats (Chasmanthium latifolium) and Eastern bottlebrush grass (Elymus hystrix), which still could make nice accents if you wanted spots with showier seed heads.

The non-native asparagus relative mondo grass (Ophiopogon), which has dark green grassy evergreen leaves and a slowly-spreading growth habit, has been successfully grown as a lawn look-alike under mature trees. I would not recommend using its cousin Liriope, the spreading form of which (Liriope spicata) can be too aggressive and is considered invasive. (Plus, it’s way over-planted.) Mondo grass thus far does not appear to be colonizing natural areas in or near Maryland.

By Miri Talabac, Horticulturist, University of Maryland Extension Home & Garden Information Center. Miri writes the Garden Q&A for The Baltimore Sun and Washington Gardener Magazine. Read more by Miri.

Have a plant or insect question? The University of Maryland Extension has answers! Send your questions and photos to Ask ExtensionOur horticulturists are available to answer your questions online, year-round.

What work can I do in the perennial garden in the dead of winter? Edging! – Featured Video

Edging the beds to control weeds and to reduce the lawn area. Plus dividing perennials that you can watch in the event of heaving during the freeze-thaw cycle. Check out this pretty, evergreen perennial – Geum ‘Totally Tangerine’!

Joyce Browning Horticulturist, Master Gardener Coordinator Video credit: Bethany Evans Longwood Gardens Professional Gardener Program Alumni; CPH

More videos on the HGIC YouTube channel

Q&A: When is it too late to transplant perennials?

Rudbeckia hirtaQ: When is it too late to transplant my flowering perennials? How late into the fall can I divide and move my plants?

A: It’s not too late! You can transplant perennials anytime until the ground freezes in the fall, or wait to transplant them in the spring. Fall is an excellent time to transplant herbaceous perennials because your plants will then have three seasons to establish a good root system before hot summer weather sets in next year. Herbaceous perennials are non-woody plants whose tops die down in the winter. They come back each year from the root system.

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