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Joe Pye weed adds a stately presence to the fall garden

September 7, 2022 • Leave a Comment

**With its large pink flowerheads, Joe Pye weed brings bold color to the fall landscape. (Eric Hofley / Michigan Gardener)**

As the hot days of summer succumb to the cool, crisp season that is fall, many gardeners choose to take advantage of this great weather for outdoor projects. Of course mums and black-eyed Susans will dominate many landscapes each September, but the huge palette of late performers is sorely overlooked and certainly deserves closer examination. Although there are many fall-blooming plants available, most remain very underused. Far fewer gardeners visit garden centers in the fall, and those that do often just look at the mums, pansies, and spring-blooming bulbs.

Great varieties of asters, anemones, pink turtleheads, toad lilies, sedum, and ornamental grasses are loaded with colorful flowers or beautifully textured foliage. Joe Pye weed (Eupatorium maculatum, syn. Eutrochium maculatum) adds large, stately flowers, a robust growth habit, and durability to your fall plant choices.

Joe Pye weed is native to North America, but is more commonly used in the finest gardens of Europe. In more dry and less fertile conditions, plants may only grow to 4 or 5 feet, but moist, fertile soil will produce plants up to 8 feet tall. Its pinkish purple flowers are produced in clusters that form larger clusters reaching up to 18 inches across. Large green leaves are attached to rich burgundy stems, resulting in a striking contrast of colors on each stalk.

How to grow

Plants prefer full or partial sun, where the stems grow strong and rarely require staking. If extensive soil preparation isn’t your cup of tea, Joe Pye weed may be the plant for you. It thrives in the moist, heavy soil conditions that are typical in mostly clay Michigan gardens. It is long-lived and extremely durable. In fact, a specimen in our display garden was once mistaken for a weed and almost completely removed. It grew back the following year and was covered with the large flowers that butterflies and bees find irresistible. Joe Pye weed spreads slowly but may eventually overstep its boundaries. This can be controlled in spring by dividing the whole clump or simply removing outside sections of the plant’s crown.

'Gateway' is a more compact cultivar of Joe Pye weed, reaching 5 to 6 feet tall. — **‘Gateway’ is a more compact cultivar of Joe Pye weed, reaching 5 to 6 feet tall. (Jonathon Hofley / Michigan Gardener)**

Companion plants

Joe Pye weed’s massive size makes it perfect to use in the back of a border. Combine it with other large, late bloomers that have contrasting colors, flower forms, and foliage. Try the blue, pink, or purple flowers of asters, especially the taller varieties like ‘Alma Potschke,’ ‘Patricia Ballard,’ and ‘Sailor Boy.’ The huge flowers of hardy hibiscus are available in reds, pinks, or white. Some rudbeckia varieties can also provide equally large plants and brightly contrasting yellow or gold flowers. For a great foliage contrast, try the silver leaves and lavender-blue flowers of Russian sage (Perovskia atriplicifolia). Position the massive architectural foliage of plume poppy (Macleaya cordata) next to Joe Pye weed for a great combination of flowers and foliage. Don’t forget ornamental grasses—some of the larger types like switchgrass, feather reed grass, or maiden grass would provide contrasting foliage and winter interest.

In your front yard, where tidy and multi-seasonal plants are desired, Joe Pye weed may have a place. Its large size and controllable vigor work well in combination with common shrubs. Its flowers fill the need for a sizable fall-blooming plant where only rose of Sharon, summersweet (Clethra), butterfly bush, and blue mist shrub (Caryopteris) are common. Other tidy and multi-seasonal perennials for the front yard include upright sedum, daylilies, hostas, ornamental grasses, and of course, groundcovers.

**‘Chocolate’ snakeroot has eye-catching, dark bronzy-purple leaves.** **(Eric Hofley / Michigan Gardener)**

Additional species

For a sturdier, more compact Joe Pye weed, the variety of choice is ‘Gateway,’ topping out at 5 to 6 feet in height. Plus, there are a few other species that are worth mentioning:

The coastal plain Joe Pye weed (Eutrochium dubium) has given us two slightly smaller introductions: ‘Little Joe’ and ‘Baby Joe’, both reaching 4-1/2 to 5 feet tall.

Hardy ageratum (Eupatorium coelestinum, syn. Conoclinium coelestinum) has blue, ageratum-like flowers on 2- to 3-foot tall plants that tend to spread.

Chocolate snakeroot (Eupatorium rugosum ‘Chocolate’, syn. Ageratina altissima ‘Chocolate’) has insignificant white flowers, but dark bronzy-purple leaves on 3- to 4-foot tall plants. ‘Chocolate’ will tolerate some shade. This foliage is incredible when contrasted with other gold, red, silver, or even green leaves.

‘Pink Frost’ (Eupatorium fortunei ‘Pink Frost’) boasts variegated leaves with white edges and pink flowers that pop when contrasted with the foliage.

These varieties, like Joe Pye weed, will tolerate moist, heavy soil, and prefer full or partial sun.

'Pink Frost' has variegated leaves with white edges and pink flowers that pop when contrasted with the foliage. — **‘Pink Frost’ has variegated leaves with white edges and pink flowers that pop when contrasted with the foliage. (Eric Hofley / Michigan Gardener)**

As fall approaches, remember that the gardening season is far from over. Gardening becomes even more enjoyable and plants tolerate being moved more easily when temperatures are cooler. Take a moment to evaluate your landscape and see where late season interest is needed. Perhaps try Joe Pye weed to add color, height, texture, and architectural interest to your fall garden.

George Papadelis is the owner of Telly’s Greenhouse in Troy and Shelby Township, MI.

Joe Pye weed

Botanical name: Eupatorium maculatum (u-puh-TOR-ee-um mack-u-LAY-tum); syn. Eutrochium maculatum (u-TRO-kee-um)
Plant type: Perennial
Plant size: 4-8 feet tall; 2-4 feet wide
Habit: Upright
Hardiness: Zone 3 or 4
Flower color: Pinkish purple
Flower size: 6- to 18-inch wide clusters
Bloom period: Late summer and fall
Leaf color: Green, with burgundy stems
Leaf size: 8-12 inches long; lance-shaped
Light: Full to partial sun
Soil: Well-drained, moist soil. Drier, less fertile soil will restrict growth.
Uses: Back of the border, architectural plant
Companion plants: Perennials: upright sedums, ornamental grasses, rudbeckia, Russian sage, plume poppy, tall asters. Shrubs: rose of Sharon, summersweet, butterfly bush, blue mist shrub.
Remarks: Tolerates heavy, clay soil. Size can be controlled with late spring pruning. Long-lived and durable. ‘Gateway’ is more compact in habit.

ELSEWHERE: More photos of Joe Pye Weed (Eutrochium maculatum)

Springtime bulb problems that you can solve in the fall

September 7, 2022 • Leave a Comment

Bulbs come up too early

If you want to avoid this problem, plant bulbs deep and don’t plant right next to a sunny south wall.

Bulb foliage may emerge during an extended winter thaw, or come up far enough during an early spring heat wave that we worry it will freeze when normal temperatures return. Relax. That plant may lose leaf tips to the cold, but it’s no big loss. A fully grown tulip or daffodil leaf may be 12 inches long. If it loses an inch at the tip—that part which sits above the zone protected by radiant heat from the soil—the remaining 11 inches is enough to fuel the plant’s growth and bloom.

A hard freeze can hurt if it comes after your bulbs’ flower buds emerge. If a hard freeze is forecast, you can cover bulbs with floating row cover cloth or newspaper to trap ground heat, or run sprinklers during the coldest hours to protect the plants via heat released by cooling water.

Some bulb species are prone to early growth (Dutch iris is an example). If you see a bulb act this way in your garden every year, don’t plant that species or variety anymore. Also, some places are more likely than others to heat up early. Beds along south-facing brick walls are at risk, as are sandy beds that slope south. Recognize these places and don’t grow bulbs there. Finally, some practices contribute to early rising. The most common is too-shallow planting.

Bloom one year, never again

Avoid this by planting your bulbs in full sun this fall. Where it’s already a problem, make site changes to let in more light or move the bulbs.

Most often, failure to bloom means a site is too shady. To flower, most spring bulbs need at least six hours of sun while their leaves are green. Given that, embryonic flower buds form in the bulb this summer to bloom next spring. New bulbs coming from a sunny bulb production field may have enough stored energy to bloom their first spring even in shade. From then on, it’s all downhill.

Shallow planting and summer moisture can also contribute. This is especially true of bulbs that have a tunic (a paper-like covering), such as tulips, daffodils, crocus, and gladiolas. Tunicate bulbs require hot, dry summers. When these bulbs are too cool or moist during summer, they may not form flowers.

The stems flop over before the plants bloom

These daffodils flopped when temperatures dropped suddenly one April day from the 70s to the teens. Within days, they were standing tall and blooming cheerily again. If, however, your bulbs flop even in good weather, the advice below is what you need.

In answer to this problem, select sunny spots for your bulbs, keep those beds well watered this fall and again next spring as the bulbs emerge, and use only slow-release fertilizers.

For example, daffodils might have stems that are not strong enough to support the weight of the flower. They either lean over from the base or bend right in the middle of the stem. On the double-flowered varieties, the weight of the bloom may cause the stem to break.

Weak stems are often the result of planting where there is too much shade. For example, daffodils need at least eight hours of sunlight to perform well. When the area is too shady, they often stretch to reach the sun, causing their stems to elongate and become weak.

As far as nutrition is concerned, “balanced” fertilizer is another possible culprit. Daffodils need a slow-release nitrogen in smaller quantities. Too much nitrogen will cause the bulbs to produce lots of weak, green leaves at the expense of blooms. The addition of more potash (potassium) will help produce stronger bulbs, which develop stronger leaves and stems.

Sufficient moisture is critical to daffodils—in the fall to help generate good roots before the ground freezes and again in the spring when the flowers are actively growing. Daffodil stems are hollow and when there is enough moisture, the stem is filled with water, which helps to support itself and the flower. If it’s dry and the stem is hollow, it is more likely to buckle under the weight of the flower.

Leaves emerge fine but quickly discolor and die

Let it be a lesson this fall: If drainage is not perfect, don’t plant bulbs there.

In these cases, the plant also fails to bloom. Bulb rot is often the cause, and poor drainage is the most common contributor to rot. Dig out the suspect bulbs. If the bulbs or roots are discolored and have soft or foul-smelling areas, dispose of them in a hot compost or by burning. Improve the drainage in that area, raise the bed, or switch to plants more tolerant of wet soil. For instance, quamash (Camassia) is generally more tolerant of moisture than tulips.

Failure to exit gracefully

Plan in the fall for a better ending to next spring’s show.

Gardeners love bulbs’ spring show but often hate the clutter factor—the leaves’ prolonged fade. Yet foliage can be clipped away earlier than you may think, if a plant is already full enough. If all you ask is that a plant replace itself each year, not increase its clump size, cut back tulip and daffodil foliage as early as June 1—about two months after the plants emerge from winter rest. If such plants don’t bloom as well the next year, stall that year’s cut by two weeks or replace them with a variety that can put up with our impatient ways.

However, it is simplest to let bulb foliage die back naturally. You can allow this yet reduce the visual distraction by pairing bulbs with late-emerging perennials such as hardy hibiscus (Hibiscus moscheutos) or blue mist flower (Conoclinium coelestinum), or self-sowing annuals such as balsam (Impatiens balsamina) or spider flower (Cleome).

Beneath this kousa dogwood are hundreds of squill (Scilla siberica) that color the lawn blue in April and then are mowed down when lawn clipping begins. Here in late April the squill leaves still show like coarser blades of grass. Even easier, for both gardener and tree: Smother the lawn and then plant the late-emerging, August-blooming groundcover hardy plumbago there (Ceratostigma plumbaginoides) to cover the squills' exit. — Beneath this kousa dogwood are hundreds of squill (*Scilla siberica*) that color the lawn blue in April and then are mowed down when lawn clipping begins. Here in late April the squill leaves still show like coarser blades of grass. Even easier, for both gardener and tree: Smother the lawn and then plant the late-emerging, August-blooming groundcover hardy plumbago there (*Ceratostigma plumbaginoides*) to cover the squills’ exit.

Article by Janet Macunovich and photos by Steven Nikkila, www.gardenatoz.com.

ELSEWHERE: Naturalizing spring flowering bulbs

Deadline nears for Michigan Big Tree Hunt contest

August 8, 2022 • Leave a Comment

ReLeaf Michigan, the only statewide non-profit tree planting and education organization in Michigan, has launched its 15th biennial Michigan Big Tree Hunt contest. The contest, which offers prizes for identifying the biggest trees in Michigan, is open to participants of all ages.

The largest trees in the state can be found anywhere: a backyard, a local park, or a hiking trail. ReLeaf Michigan awards certificates and prizes for the largest tree submitted from each county, for the overall largest tree in different age groups, and for potential state champion trees. Even if the tree submitted is not as large as the currently listed state champion of that species, it’s important to still submit, since the current champion may have died or since been removed.

ReLeaf Michigan started the Michigan Big Tree Hunt in 1993 to celebrate our state’s beauty and create a fun way to gather information about Michigan’s biggest trees. The contest is an opportunity for all age groups to help track these vital historical living landmarks.

More contest details and the entry form are available at www.bigtreehunt.com. Entries are due by August 19, 2022. For questions not answered on the website, please email bigtreehunt@releafmichigan.org or call 800-642-7353.

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