6 Perennials for Spectacular Fall Color


Cushion mums are as spectacular in bloom as any summer perennial. Photo: Rachel Kramer, flickr

You thought the gardening season was over by September and all you had to do was hang up your gardening tools? Think again! Thanks to climate change, in most regions autumns are longer and warmer than ever and that has extended the flowering season well into November, often even December.

Bulbs (colchicums and autumn crocuses), shrubs (several hydrangeas, seven-son flower [Heptacodium] and common witch-hazel) and many annuals (pansies, snapdragons, hybrid sweet alyssums, etc.) will continue to bloom right through the fall, even sailing through the first light frosts. They won’t stop until a truly hard frost hits. In fact, some annuals, like ornamental cabbage, don’t even start to show color until September. But there are more fall-flowering varieties among perennials than in any other group.

Here are six of the best!

Garden Mums

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Hundreds of years of hybridizing have led to the popular “cushion mum,” with a dense, dome-shaped habit and hundreds of flowers. Photo: pixabay

There are currently about 20 species of Chrysanthemum, commonly called chrysanthemums or just mums, and all are fall bloomers. However, just because they are sold locally doesn’t mean they are hardy in your region.

Many merchants make little difference between florist chrysanthemums (frost-tender varieties) and garden mums (hardy varieties) and sell pots of both in the fall. The two, after all, belong to the same species (Chrysanthemum × morifolium, formerly C. × grandiflorum and Dendrathema × grandiflorum), a complex hybrid with both hardy and subtropical species in its background. Florist and garden mums may therefore appear to be identical, but florist varieties are often only hardy to zone 8 whereas hardy garden mums are solid in gardens as cold as zone 3. That’s a huge difference!

So, how can you tell the two apart in a store display?

In box stores, supermarkets or other non-specialist venues, you can’t. Chances are all the mums they sell are florist varieties, shipped in from the South in full bloom for rapid fall sales. They’re essentially annuals in most gardens. However, garden centers and plant nurseries  usually offer both garden and florist types. To find out which is which, ask about guarantees. Truly perennial mums will have a 12-month guarantee; tender florist mums won’t.

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Hardy chrysanthemum Mammoth Red Daisy is a big one, as large as many shrubs! Photo: Ball Horticultural Company

There are some very good garden mums (i.e. hardy cushion mums) out there, varieties known for their resistance to extreme cold, and this includes the Morden, Minn, Firecracker and Mammoth™ series (the latter was formerly known as the My Favorite™ series and that name may still be used by some nurseries). The four series offer single and/or double varieties in a wide range of colors: yellow, orange, pink, purple, white, etc. The Morden and Minn mums are dwarf plants (12-18 inches x 18-24 inches/30-45 cm x 45-60 cm) covered with flowers from September to frost, while the Mammoth series mums are taller and wide: 3 to 4 feet (100-120 cm) tall and wide. Firecracker series mums (Power Surge®, Showbiz®, Suncatcher®, etc.) are of intermediate size.

All varieties mentioned are hardy to zone 3. Sun or partial shade.

Heirloom Mums


The most popular heirloom mum is ‘Clara Curtis’. Photo: rosekennedygreenway.org

There are also heirloom mums, also called old-fashioned mums or rubellum mums. They’re a different species: Chrysanthemum × rubellum, formerly C. zawadskii latilobum.

This group includes the well-known ‘Clara Curtis’ (pink, zone 3), ‘Duchess of Edinburgh’ (dark pink, area 4) and ‘Mary Stoker’ (yellow, zone 3), plus half a dozen others. All produce simple daisylike flowers with a yellow center. They reach about 18 to 30 inches (45-75 cm) in height and diameter, depending on the cultivar, but have more finely cut leaves than garden mums and certainly don’t form the dense mounds typical of cushion mums. Instead they have a much more open habit and are even inclined to wander a bit. They’re not really invasive, though, as it’s easy to pull out stragglers if they go too far.

Zone 3. Sun or partial shade.

You can read more about hardy mums here: Chrysanthemums for Cold Climates.


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New York aster ‘Patricia Ballard’. Photo: dorsetperennials.co.uk

North American fields and forests are full of wild asters in shades of violet and white, but there also are many cultivated asters to be discovered, including New England asters (Aster novae-angliae, now Symphotrichum novae-angliae) and New York asters (A. novi-belgii, now S. novi-belgii). They have larger flowers in a much wider color range than wild asters. They come in shades of violet (so-called blue), purple, pink, red, and white, often with semi-double or double flowers.

Until recently, most asters were tall to medium-height plants for the back or the middle of the garden. A. n-a. ‘Harrington’s Pink’ (pink, 48 inches x 24 inches/120 cm x 60 cm) and A. n-b. ‘Patricia Ballard’ (dark pink, 36 inches x 15 to 20 inches/90 cm x 40-50 cm) are examples of these popular taller varieties.

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Aster ‘Purple Dome’. Photo: Footprints Plants, LLC

Dwarf asters, although often sold under the botanical name A. dumosus (a name that really belongs to a summer-flowering Eurasian species), are actually just smaller selections of A. novae-angliae and A. novi-belgii. A. n-a. ‘Purple Dome’, for example, is popular, forming a rounded dome 16 to 20 inches (40-50 cm) in height and width with purple flowers. The Wood’s series of dwarf asters is similar, but comes in other colors.

Fall asters are hardy to zone 4, sometimes in zone 3. Sun or partial shade.


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Solidago rugosa ‘Fireworks’. Photo: F. D. Richards, flickr

There is a surprising dichotomy between the attitude of North American and European gardeners towards goldenrod (Solidago spp.). North Americans tend to see goldenrods, which are native to their continent, as weeds and want little to do with them. Europeans, on the other hand, for whom they are exotic plants coming from the New World, adore them!

I find it almost criminal to malign these gorgeous perennials with their rich yellow flowers simply because they’re natives when, in fact, they are among the best fall perennials. True enough, Canada goldenrod (Solidago canadensis) is highly invasive species in gardens, both through seeds and wandering rhizomes, but the others are clump-forming and stay put. If you don’t believe me, try S. × ‘Crown of Rays’ (23-27 inches x 18-23 inches/60-70 cm x 45-60 cm), S. × ‘Dansolitlem’ Little Lemon® (12-18 inches x 12-23 inches/30-45 cm x 30-45 cm) or S. rugosa ‘Fireworks’ (36-48 inches x 36 inches/90 to 120 cm x 90 cm), all with stunning feathery yellow flowers. Beautiful!

Zone 3. Sun or partial shade.

Autumn Sedum

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Sedum ‘Herbsfreude’. Photo: laidbackgardener.blog

Autumn sedum, also called autumn stonecrop, showy sedum or showy stonecrop (cultivars and hybrids of Sedum spectabile [Hylotelephium spectabile] and related species), is a fairly low-growing plant (rarely more than 2 feet/60 cm tall), with succulent stems and leaves, often bluish green. The star-shaped flowers are produced in dense masses, a bit like colored cauliflower, and come in shades of pink, red or white, more rarely, pale yellow. They’re one of the last fall feeding stations for butterflies.

S. ‘Herbsfreude’ (‘Autumn Joy’), 12-24 inches x 18-24 inches (60 cm x 45-60 cm), is best known and bears pink flowers turning brownish red. S. ‘Autumn Fire’ is similar, but more compact (20 inches x 18-24 inches/50 cm x 45-60 cm). A sturdier plant, it doesn’t tend to flop under the weight of its flowers the way ‘Herbstfreude’ may do. S. ‘Purple Emperor’ (16 inches x 18-24 inches/40 cm x 45-60 cm) is just one of many autumn sedums with dark purple leaves and pink flowers, while ‘Elsie’s Gold’ (16-18 inches x 20-24 inches/40-45 cm x 50-60 cm) has green leaves with yellow to cream edges and magenta flowers. It’s less likely to flop than most other variegated autumn sedums.

There are dozens of other excellent varieties.

Zone 3. Sun.


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Chelone lyonii ‘Hot Lips’. Photo: laidbackgardener.blog

Turtleheads get their curious name from their flowers, said to look like a turtle’s head. In fact, their botanical name, Chelone, comes from the Greek and also means turtle.

Red turtlehead (Chelone obliqua) is probably the most common variety. It produces a dense, non-invasive clump of solid, perfectly erect stems 24-36 inches tall on a plant 24 inches in diameter (60-90 cm x 60 cm). The very dark green leaves are attractive all summer, but the beautiful deep pink flowers dominate in the fall.

Lyon’s turtlehead (C. lyonii) is very similar in all respects: you can scarcely tell it apart from pink turtlehead (C. obliqua). C. lyonii ‘Hot Lips’ (60-90 cm x 60 cm) is very popular with darker leaves than the species. C. lyonii ‘Tiny Tortuga’ is a dwarf variety only 12-15 inches tall and 8-10 inches in diameter (30-40 cm x 20-25 cm).

Zone 3. Sun or shade.

Maiden Grass

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Miscanthus ‘Purpurascens’. Photo: laidbackgardener.blog

This tall grass (Miscanthus sinensis) is very popular, grown for its arching green ribbon-shaped leaves that become straw-colored in fall and its blooms that start pinkish to become silver-white as fall progresses. Both leaves and flowers hold on right through the winter into spring, offering six months or more of interest.

In zone 7 and above, maiden grass can self-sow and become invasive due to overseeding, so look for near-sterile varieties like ‘Autumn Light’ and ‘Morning Light’ as well as any of the variegated cultivars, as they almost never bloom.

Seeds don’t mature in cold climates, so maiden grass isn’t invasive there … but it might not perform well there either. Its hardiness varies from zone 4 to 6, so make sure you choose one cold resistant enough for your conditions. Also, some cultivars won’t have time to bloom in short-season climates or will only bloom occasionally in years where the summer was extra-long. Unless your local merchant is a specialist in ornamental grasses, you won’t be warned about this fact, so research your plants ahead of time.

Best choices for bloom in colder climates include the extra=hardy Huron series, including M. s. ‘Huron Sunrise’ (6 feet x 2-3 feet/180 cm x 60-90 cm), zone 3, the popular tall cultivar M. s. ‘Silberfeder’ (7-8 feet x 4 feet/200-250 cm x 120 cm), zone 4, and purple maiden grass (M. ‘Purpurascens’), 5 feet x 2 ½ to 3 feet (150 cm x 75-90 cm), also zone 4. The latter offers distinctly coppery foliage color in fall.

Sun or partial shade.

Even More Fall-bloomers

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Add the right fall-bloomers and your autumn garden will come alive!: Photo: autumnasters.co.uk

There are still many other perennials that bloom in fall: boltonia (Boltonia), Japanese anemone (Anemone × hybrida), helenium or sneezeweed (Helenium), bugbane (formerly Cimicifuga, now Actaea), ironweeds (Vernonia), tall coreopsis (Coreopsis tripteris), Joe-pye weeds (Eupatorium), perennial sunflowers (Helianthus ‘Lemon Queen’ and others), black-eyed susans (Rudbeckia), monkshoods (Aconitum), echinaceas (Echinacea), and many more.

As you can see, with the right choice of plants, there is no reason why your garden can’t be as spectacular in October as it was in July!20170911a-rachel-kramer-flickr


Beautiful Flower, Strange Name


Chelone obliqua

Among the stars of the fall garden is a truly unique perennial, the turtlehead (Chelone spp.). What I love about this plant, besides its long-lasting flowers, is its perfect behavior. It never runs, flops, or fades, standing firm in the worst wind and the deepest shade. If only all the plants were as well behaved!


The curious flower is said to resemble a turtle head!

At the very end of the summer and throughout the fall, fat tubular pink to white flowers appear on short spikes atop each stem. The blooms are odd enough in appearance, almost closed at the tip with an opening resembling a beak. They’re said to look like the head of a turtle, whence both the common name and the botanical one, as Chelone (pronounced “kay-LOH-nee”) is Greek for turtle.

The curious flower is designed to let only the strongest pollinators enter, notably bumblebees and hummingbirds. Even so, you’ll often see butterflies stopping by, trying to steal a bit of nectar with their long proboscis.

Turtleheads leaves have opposite leaves with each pair placed at a 90 degree angle to the pair below, giving the effect of a cross when you look at the plant from above. Their stem is square, a trait unusual in their plant family, the Plantaginaceae (foxglove family), but one shared with at least one close relative, the obedient plant (Physostegia virginiana).

There are only four species of turtlehead, all from eastern North America. The following three are the most widely available to home gardeners.

Red Turtlehead (C. obliqua)


Chelone obliqua

In spite of its common name, the deep pink flowers of this species not really much darker than those of the so-called pink turtlehead (C. lyonii) with which it is often confused. This species is native to eastern and central United States, although absent from New England.

Red turtlehead forms dense clumps of upright unbranching stems bearing large, lightly toothed, lanceolate leaves of a very dark green shade. The leaves have a short petiole, an apparently minor detail, but one worth pointing out, as that is what distinguishes it from C. lyonii.

Red turtlehead reaches about 2 to 3 feet (60 to 90 cm) in height. As with the other turtleheads, it begins to bloom at the very end of summer and continues for a good 2 months, right through fall in many locations. It is hardy to zone 3.

There is also a supposed white-flowered cultivar of this species called ‘Alba’… but it is likely just C. glabra, described below.

Pink Turtlehead (C. lyonii)

Chelone obliqua

Chelone lyonii

Essentially identical to C. obliqua from a gardener’s point of view, with the same pink blooms, you can identify pink turtlehead by the slightly longer leaf petioles. It is also somewhat taller (2 to 4 feet/60 to 120 cm) than C. obliqua.


Chelone lyonii ‘Hot Lips’

The most common cultivar of this species is ‘Hot Lips’, which is a more compact plant: about 2 to 3 feet (60-90 cm) in height. Its flowers are a darker pink and its stems are reddish.

‘Tiny Tortuga’ is a 2014 introduction, with dark pink flowers. Very dwarf, it reaches only 14 inches (35 cm) high.

There is also another dwarf variety, ‘Pink Temptation’, about 16 inches (40 cm high). All these plants are hardy in zone 3.

White Turtlehead (C. glabra)


Chelone glabra

This is the most widely distributed turtlehead, found throughout much of eastern and central North America well into Canada. It is easily distinguished from the others by its white to white tinged pink flowers. Also, the leaves are narrower and sessile (they have no petiole at all).

Although a plant of swampy woodlands in the wild, white turtlehead grows very well in ordinary garden soils. Its height is highly variable, from 3 to 6 feet (90-180 cm): it grows tallest in water-logged soils. Although native well into the North, it seems no hardier than the southern species: zone 3.

I find this species the least interesting turtlehead for the flower border, because its flowers are less dense, tend to brown quickly and its habit is more open and less sturdy. It is even a bit invasive.

There is also a cultivar, C. glabra ‘Black Ace’, with extra dark foliage, almost black, and the denser flowers. Also zone 3.

Japanese False Turtlehead (Chelonopsis yagiharana)


Chelonopsis yagiharana

Chelonopsis is the Asian counterpart of the genus Chelone, with a very similar habit and foliage, but its tubular flowers are distinctly trumpet-shaped and thus look nothing like a turtlehead. The lower lobe is substantially longer and wider than the upper one.

There are over 15 species, but the only one I have seen offered is C. yagiharana, from Japan. This species is quite compact: about 1 to 2 feet (30-60 cm) in height. Its exact hardiness is not known yet, but it seems to perform well in zone 4. It is as yet rarely offered.

Growing Turtleheads

One nice thing about turtleheads is that they are a snap to grow and you never hear complaints about them.

They like soil rich in organic matter that is always a bit humid. They tolerate poorly drained soils and can thus grow along the edge of a water garden. Water them in case of drought, however, as their drought tolerance is limited. A good mulch to keep their soil more evenly moist would be appreciated.

They are not very heavy feeders and will get along fine with an annual application of compost.

Turtleheads seem to grow equally well in sun or shade… and how often can you say that about a plant! In the wild, they are often found in dense forests where little light penetrates, but also in swamps out in full sun. Just make extra sure they are well-mulched if you want to grow them in a sunny location.

Most species of turtlehead form a dense clump that expands ever so slowly in diameter, so keeping them in their place is not complicated. White turtlehead is the exception, a faster grower with a more invasive nature and may require more frequent division.

For quick and easy multiplication, try taking stem cuttings. You can also divide the plants, preferably in the spring, but also in the fall.



Baltimore Checkerspot

Turtleheads are the primary host of the beautiful Baltimore Checkerspot butterfly, but the damage is usually limited to a few leaves and thus easily forgiven. And even though they often they grow in damp environments where slugs are numerous, the latter seem to have no interest in turtleheads.

Sadly, white-tailed deer are crazy about this plant: if you have a problem with this mammal in your yard, turtleheads will not be a good choice for your flowerbeds!

Where to Find Them?

Turtleheads are quite widely available and most garden centers and nurseries will offer at least one variety, although you’re not likely to find the whole range of species and cultivars in a single spot. For specific cultivars you can’t find locally, try a mail order source.

Turtleheads: their odd name belies an ease of culture well worth discovering, certainly one of the best fall-blooming perennials.