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PLEASE NOTE: In the autumn of 1995, we hatched the idea for a free, local gardening publication. The following spring, we published the first issue of Michigan Gardener magazine. Advertisers, readers, and distribution sites embraced our vision. Thus began an exciting journey of helping our local gardening community grow and prosper.
After 27 years, nearly 200 issues published, and millions of copies printed, we have decided it is time to end the publication of our Print Magazine and E-Newsletter.

Archive for the perennials tag

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.
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)

Filed Under: Plant Focus Tagged With: fall, fall flowering perennial, Joe Pye weed, perennials, plant focus

Can rabbit manure be used as mulch around plants?

March 11, 2021   •   Leave a Comment

We have a pet house rabbit that is litter trained. Can the manure and litter (made from recycled newsprint) be used as mulch in a perennial bed or around trees and shrubs?

This sounds like a gold mine since rabbits are vegetarians. But it comes with significant cautions. Rabbit manure is higher in nitrogen than even chicken manure. It also contains phosphorus. Nitrogen is great for leaf production. The phosphorus is good for fruit and flower production. So consider exactly what you will be enhancing with its application. Average N-P-K (nitrogen-phosphorus-potassium) analysis of composted rabbit manure is 2-1-0.8, which is relatively low compared to other commercial products. In order for the manure to be useful, it must be hot composted, preferably for a year, to reduce the probability of transmitting any pathogens lurking in the litter. A hot compost pile should measure at least 150 degrees in temperature.

Composting the litter changes the material into a form plants can better use. It also allows odors to dissipate. After the year-long composting, it should be applied to the soil in late fall and worked in. Preferably, it should not be used as mulch and never uncomposted, as the high level of nitrogen can actually burn and damage plants, even with the newsprint base. Since it has to be worked into the soil to be effective, you might find this easier with your perennial bed in fall than disturbing the roots of trees and shrubs.

Related: Bunny honey – Using rabbit manure as a fertilizer

Filed Under: Ask MG Tagged With: litter, manure, mulch, perennials, rabbit, shrubs

What are some suggestions for deer-resistant plants?

December 15, 2018   •   Leave a Comment

My subdivision has been taken over by deer. As I plan next year’s garden, please suggest some perennial flowers or shrubs that deer will not eat.

If deer are hungry enough, they eat just about anything. This answer will include deer-resistant or rarely-damaged varieties and resources to check out more. You might first consider deterring deer from entering your garden. One suggestion is a motion-sensitive sprinkler, called the ScareCrow, which is available at many garden centers. It sprays a shocking blast of water about twenty feet, scaring away deer. Move it periodically or the deer “learn” the pattern, but it is harmless and waters your plants. Be sure to turn it off if you have guests! Also, deer do not like prickly items, many fragrant plants, and footing areas that make noise or feel unstable.

Here are some plants that deer tend to avoid. Bulbs: allium, daffodil and autumn crocus. Herbs: dill, purple coneflower, lavender, sage, tansy, thyme. Shrubs: boxwood (Buxus sempervirens), American holly (Ilex opaca), and Japanese pieris (Pieris japonica). Trees: paper birch (Betula papyrifera) and Colorado blue spruce (Picea pungens). Perennials: yarrow, columbine, bergenia, bleeding heart, oriental poppy, Russian sage, coneflower (Rudbeckia), lambs’ ears (Stachys byzantina), and yucca. Groundcovers: sweet woodruff, dead nettle (Lamium maculatum), plumbago (Ceratostigma plumbaginoides), and pachysandra.

Deer-Resistant Plants for Homeowners is a 2008 publication by Michigan State University, Bulletin E-3042. Contact your county extension office for a copy (www.msue.msu.edu). Also try the book Deerproofing Your Yard & Garden by Rhonda Massingham Hart (Storey Publishing).

Filed Under: Ask MG Tagged With: deer, perennials, resistant, shrubs

Janet’s Journal: When Tolerance is Not a Virtue

July 3, 2018   •   3 Comments

Rather than placing plants where they only “tolerate” a space, plant them where they are actually happy

For the best garden, avoid the word “tolerate” as you select plants. Use what will thrive on a site, not just survive. Barberry, German statice, lavender, dianthus and iris can all thrive in the dry soil.
For the best garden, avoid the word “tolerate” as you select plants. Use what will thrive on a site, not just survive. Barberry, German statice, lavender, dianthus and iris can all thrive in the dry soil.

Why do we deliberately plant species that only “tolerate” our gardens? Perhaps it’s because “shade tolerance,” “heat tolerant,” “tolerant of a wide range of conditions” and similar phrases are basic to horticulture. It’s so common in books that we skip right over this important word as we read.

Maybe we just don’t recognize body language in plants as well as we do in people. A plant’s message may reach us on a subconscious level and trigger vague disquiet, but for most it doesn’t process beyond that point.

Are you in tune, or are you living in a garden full of sullen, sniveling, grumbling malcontents? Here’s a primer, a listing of some of the signals I’ve learned to read as “I’d rather not be here but if you insist I’ll stay and make us both miserable.”

Rodger’s flower (Rodgersia sambucifolia) is far less tolerant of drought than lamium, and unable to stand the full sun, crying out with scorched leaves.
Rodger’s flower (Rodgersia sambucifolia) is far less tolerant of drought than lamium, and unable to stand the full sun, crying out with scorched leaves.

There may be fine line divisions in your garden between tolerable an intolerable sites. Sweet Solomon’s seal (Polygonatum odoratum ‘Variegatum’) is a stalwart performer here where the lilac shades it all afternoon, yet would fall prey to pests and disease in the full sun and heat just a few feet to the left.
There may be fine line divisions in your garden between tolerable an intolerable sites. Sweet Solomon’s seal (Polygonatum odoratum ‘Variegatum’) is a stalwart performer here where the lilac shades it all afternoon, yet would fall prey to pests and disease in the full sun and heat just a few feet to the left.

Astilbe is a tough plant all around, so long as it doesn’t have to go dry. Given constantly moist soil, it can put on a show even while putting up with singed leaves in full sun.
Astilbe is a tough plant all around, so long as it doesn’t have to go dry. Given constantly moist soil, it can put on a show even while putting up with singed leaves in full sun.

Clematis suffers from its reputation as “tolerant of shade.” Here, it’s tolerating shade as it always has, by escaping over the fence to bloom in the sun, in the yard outside the gardener’s view!
Clematis suffers from its reputation as “tolerant of shade.” Here, it’s tolerating shade as it always has, by escaping over the fence to bloom in the sun, in the yard outside the gardener’s view!

Subsisting in Shade

A key to recognizing tolerance is knowing what a plant could look like. Until you see a member of a species being all it can be, you may not register your flora’s resentment of the conditions you force it to endure. You may never hear the mumbled curses shared between pallid plants who view you as the stingy human who’s consigned them to, in this first case, chronic light deficiency.

Perhaps the plant that opens your eyes is one of your own that escaped by seed or runner into a brighter place, to stun you with its transformation. Although I’ve also seen this happen where the gardener does not even recognize the original and its progeny as the same species. Maybe your enlightenment comes when you see a division of your plant in better circumstances, strutting its stuff in someone else’s sun garden. The differences, minor or major, and the chance for comparison might escape you except the resident gardener is there, thanking you for the gift of (name of plant here) and bragging on its performance.

What a shade-tolerant plant does is become thin, developing more stem and fewer leaves. The stalks may be weak so the plant dips and sags. Its yearning for sun may make it lean or even crawl toward the light on prostrate stems. The foliage lacks substance and is paler than it should be. In the case of variegated foliage that longs for the sun, golds may become dull green, maroons a muddy pink, and gray loses its silvering fuzz to reveal ordinary green.

Flowers, too, are paler. Worse, they’re fewer in number despite all you spend on “bloom builder” fertilizers.

Some shade tolerant species whose discontent becomes obvious in midsummer:

Daylilies – come on, count the flowers per stem and then try to tell yourself it’s happy compared to sun-grown siblings!

Purple coneflower – snip a flower from your shade-grown echinacea and put it in a vase with one cut from the sun garden.

Balloon flower – this sturdy creature shouldn’t require staking but it will fall when it’s starving for light.

Sullen in the Sun

Their foliage wilts on hot days and has a hang-dog droop even when it’s only pleasantly warm—these plants are begging you for a place with at least midday shade. A leaf’s edges may be scorched, while the blade is pale and chlorotic, its color-producing chemicals destroyed by light as surely as sun fades a drapery. Singed, washed out foliage may be concentrated at the top of the plant or on its sunniest side, that outer rank of leaves taking the brunt of the abuse. Flowers may be abundant but short-lived. The whole plant may opt for a shorter season, in the case of woodland and forest-edge species able to escape into dormancy.

Hostas are troopers, making only the smallest unhappy noises in the sun. Not so, flowering dogwoods and rodgersias, who moan and wail for cool shadow. Lucky bleeding heart and mayapple can fold their foliage early and depart the scene by midsummer.

Whining in the Wind

Holding shredded, tattered flower petals or snapped flower stalks out for you to see, your “wind tolerant” plants can’t believe you fail to notice their plight. Some are less stoic, simply refusing to flower or, if woody, holding back growth on their exposed faces until the windward side is all stunted, twiggy limbs. Other shrubs and trees thrust dead branches in your face, hoping you’ll understand that constant rocking in the wind is costing them roots.

A more subtle sign is foliage that’s been rattled and rubbed against itself until it’s bruised, creased, abraded and wide open to every leaf spot fungus that ever took a liking to that kind of plant.

Serviceberry is wind tolerant, but don’t ask it to endure too much if you expect to enjoy its fragrance or cut a pristine flowering stem for a vase. Poplars stand up to any gale but try not to look at their spotted leaves and cankered twigs, and don’t hold it against them when those twigs grow into easily broken limbs. Great Plains gardeners know lilacs as dependable windbreaks, but don’t send a photo of your symmetrical shrub to your gardening cousin in Kansas, if you want him to remain deaf to his deformed lilac’s moans. And certainly don’t cut a bunch of big, rich-colored blooms from your shrub and drive them out to him, unless you want him to learn to cry over his plant’s paltry showing.

Hostile in the Heat

Plants that don’t love heat, only tolerate it, cry out in singed spots, especially on wide, horizontally oriented leaves. They wilt on the worst days and even on the best days curl their foliage under like so many clenched fists. With every stab from their ever-present mites, they hurl silent curses at the gardener. If all else fails, the herbaceous ones will develop crown rot, tender young buds drying and dying as they emerge, and the plant will bow out.

Many people ask their plants to tolerate heat without knowing it. Away at the office, you may not notice the midday sun or superheated 3 p.m. air that oppresses your Hydrangea, pounds your Pulmonaria, and cooks your Caladium.

Dreadful in Dry Places

Brief bloom, slow growth, increased susceptibility to fungus and sucking insects, tip dieback—these are all the price we ask a plant to pay when it must tolerate drought.

Just because it puts up with the shade, don’t ask it to take the drought, too, or Astilbe will simply retract its developing flower buds in crisped disappointment. Spirea is a dogged player, even where it’s dry—just don’t expect it to put on any but the briefest floral show. Misunderstood Monarda, grown dry for fear of wetting its mildew-prone leaves, will powder up even sooner than otherwise. Given constant moisture the same plant may show not a spot of gray.

Pests can tell a plant that’s being tolerant, even if we can’t see any difference. Above, this butterfly weed (Asclepias tuberosa) growing in compacted soil at roadside may look fine at first glance...but it regularly falls prey to aphids (below) that never touch its sister plants growing 10 feet away in deeper, better drained soil.
Pests can tell a plant that’s being tolerant, even if we can’t see any difference. Above, this butterfly weed (Asclepias tuberosa) growing in compacted soil at roadside may look fine at first glance…but it regularly falls prey to aphids (below) that never touch its sister plants growing 10 feet away in deeper, better drained soil.

butterfly-weed-attacked-by-aphids-0718

Muttering in the Mud

Listen early in the year for the voices of plants who want out of the wet soil. They give themselves pep talks and start into growth, then gasp as stems are bitten by crown rot and fall. Surviving stems bear pale and discolored leaves, deprived of nutrients available only in warmer or better-aerated soils. Leaf spot and mildew plague them, especially at high summer.

Burning bushes and yews must be the most tolerant plants of all time, for all the places they’re asked to grow. But watch them to be the first to tell you when it’s too wet, with pale foliage that yellows or develops fall color early. Redtwig dogwood, a native to wet places where soil water is constantly refreshed, is often relegated to stagnant mud where its beautiful foliage assumes a tortured, pocked look.

Don’t scoff at intolerance of confinement. Look closely at the bee balm (Monarda ‘Violet Queen’) in the center of this picture. See the brown, thin, stunted, bloomed-out stems to the right? That’s her mother plant, the only difference between the two being that the daughter is a division, set into fresh soil renewed with compost.
Don’t scoff at intolerance of confinement. Look closely at the bee balm (Monarda ‘Violet Queen’) in the center of this picture. See the brown, thin, stunted, bloomed-out stems to the right? That’s her mother plant, the only difference between the two being that the daughter is a division, set into fresh soil renewed with compost.

Crabby in Confinement

Some aspects of a plant’s environment are quite natural, others almost entirely manmade. Confinement, for instance: forcing a plant that wants to spread to stay put, or restricting a woody plant that wants to stretch its roots to a small pot.

We must confine plants to be able to grow trees in openings in the sidewalk or perennial gardens in patio containers. That’s all copasetic so long as we understand the unavoidable consequence of limited space: premature aging. Wood ages and dies sooner, herbaceous stems become more crowded more quickly, leaf size diminishes on older limbs and crowns, and diseases multiply as blooms decrease.

So star magnolia and callery pear will perform acceptably where their root space is limited, but to keep them flowering well, prune regularly to stimulate fresh young growth. Mint makes a great container plant, lush and fragrant even on a hot patio, but where one in the garden might need dividing every two or three years, divide the potted one each and every spring.

If I were a plant, I would probably tolerate much in exchange for compliments and the satisfaction of persisting against all odds. Yet I doubt that I could handle confinement with anything approaching grace, for there as here I would always want a little more space!

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

Filed Under: Janet’s Journal Tagged With: conditions, Janet Macunovich, Janet’s Journal, moisture, perennials, soil, tolerance

Janet’s Journal: Double Your Perennials, Double Your Fun

June 5, 2018   •   Leave a Comment

Pair perennials properly to create superb companion plantings

Crocus, a spring-blooming lark, has an additional qualification for doubling up: It has a shallow root and so can be paired with tap-rooted myrtle euphorbia (Euphorbia myrsinites).
Crocus, a spring-blooming lark, has an additional qualification for doubling up: It has a shallow root and so can be paired with tap-rooted myrtle euphorbia (Euphorbia myrsinites).

Quamash (Camassia leichtlinii) is a lark, a spring-blooming bulb of wet places. When it fades into dormancy, it can be covered by a late rising, moisture-loving owl: boneset (Eupatorium perfoliatum; foliage in the foreground). Boneset is a relative of another, better known owl, Joe Pye weed.
Quamash (Camassia leichtlinii) is a lark, a spring-blooming bulb of wet places. When it fades into dormancy, it can be covered by a late rising, moisture-loving owl: boneset (Eupatorium perfoliatum; foliage in the foreground). Boneset is a relative of another, better known owl, Joe Pye weed.

Doubling up on perennials. It’s the designer’s color-hungry attempt to copy and even improve on nature. Nature, which blankets the ground below trees with spring ephemerals and populates a prairie with low-growing vernal species among taller, later-blooming types. In both instances two perennial groups co-exist harmoniously. The spring species live fast and finish their business as the summer crowd takes over. The summer species graciously shed their leaves or topple to the ground at year’s end, letting in light to fuel the next cycle.

The designer who doubles up perennials will plant two species where one might be expected to fit, pairing them in one of several ways:

A) Larks with owls: One species that starts and finishes early in the season with another that comes on later. Larks often have a summer dormancy, or don’t suffer when the gardener cuts them back hard early, to make room for the owl.

B) Layered species: One wide, ground floor occupant below a narrow high-riser.

C) Equitable competitors: A shallow root scrambler with a deep or tap root, each drawing on different levels for water and nutrients, and the scrambler able to move out of the way as the other grows.

The concept is simple. Yet it is an attempt to copy natural elegance so it requires observation, patient trial and a certain ingenuity in execution. I coined the phrase “doubling up” for my garden design classes. So here are some successful doubles and the most important practical lessons I’ve learned along the way.

Perennial alyssum is not only a tap root plant but a ground floor specialist. Thus it doubles-up well with a shallow-rooted high riser such as Joe Pye weed (Eupatorium purpureum).
Perennial alyssum, left, is not only a tap root plant but a ground floor specialist. Thus it doubles-up well with a shallow-rooted high riser such as Joe Pye weed (Eupatorium purpureum, right).

Be a matchmaker.

In the accompanying chart are species for doubling up, each with its qualifications listed – lark, owl, ground floor, high riser, tap root or shallow-rooted scrambler. Any species that rates a check in the “lark” column (A1) is a suitable candidate for pairing with an “owl” (A2). High risers (B1) can double up with any ground floor specialist (B2). Tap roots (C1) are right to be teamed up with shallow root scramblers (C2).

Always plan for “Right Plant, Right Place.”

In making these pairings, I leave it to you to familiarize yourself with a species’ cultural requirements—amount of sun, moisture needs and soil preference. I trust you’ve already learned the lesson that it only pays to plant where you know the species will thrive, so you’ll pair off plants only if you know they both suit the site, or you’ll modify the site. For instance, oriental poppy, a lark, can share space beautifully with the owl, hardy hibiscus, but only if you can meet the former’s need for deep, well-drained soil, plus keep that soil moist enough to satisfy hibiscus, a native of damp pond edges.

Aim for more than one qualifier.

Plants get along in crowded quarters even better if they have compatible adaptive characteristics from two or even three of the categories. For example, balloon flower as a high riser does well with ground floor rock cress. You will learn to recognize the match is more sure when you see that it also pairs a tap-rooted owl (balloon flower) with a shallow-rooted free ranging species that does its growing in late winter (evergreens have that advantage!) and early spring.

I might also pair balloon flower with hybrid pinks for the high rise/ground floor match, but I’d be less confident of success. Neither is shallow-rooted so they will compete with each other more than is good. Also, because the pinks can’t scramble—i.e. move readily by surface-rooting stems into better space when conditions such as shade from a growing partner becomes greater in one spot than another—it will be a bit slow to react to openings in the balloon flower’s “canopy,” suffer more thin spots, and be less vigorous overall.

Lark and owl: The lark, Virginia bluebells (Mertensia virginica), is a great match for the owl, Japanese painted fern (Athyrium niponicum var. pictum), because both are at home in the shade.
Lark and owl: The lark, Virginia bluebells (Mertensia virginica, left), is a great match for the owl, Japanese painted fern (Athyrium niponicum var. pictum, right), because both are at home in the shade.

Plumbago (Ceratostigma plumbaginoides) is another late-rising owl, excellent for covering the departure of larks such as tulips and daffodils.
Plumbago (Ceratostigma plumbaginoides) is another late-rising owl, excellent for covering the departure of larks such as tulips and daffodils.

Wait to see who wins.

Yet you should keep an open mind as you pair the plants and avoid making snap judgments once you’re growing the doubled-up combination. Some pairings will test your determination, requiring the patient trial I mentioned earlier. I call this period “see who wins” even though what I always hope for is a long-term balance of power.

When one plant is slower growing than the other, but persistent enough to endure, it’s all a matter of time. Tap-rooted, high riser gas plant increases so slowly that it may be years before it’s a visually wonderful match with shallow-rooted, ground floor sedum ‘Vera Jameson,’ but that day is almost sure to come.

However, when the paired plants are both vigorous growers, it’s best during the wait and see period to adopt the laissez-faire of a really good kindergarten teacher. Watch and tolerate rambunctious individuals so they have leeway to grow, and step in only when one’s assertiveness becomes a threat to another’s growth. Stepping in between plants may involve judicious cutting back during the season, yearly thinning, or staking the lark to allow the owl to emerge with straight stems.

Consider once more the oriental poppy/hardy hibiscus double up. Through a wait-and-see strategy, I learned that a slow-growing pink cultivar of oriental poppy may coexist peacefully with hibiscus, but the rampant red-orange standard doesn’t play nice and will abuse a well-mannered partner if I turn my back. One year, I planted both types of poppy, each with a hibiscus companion. The pink poppy and its hibiscus are still happy campers seven years later, without any interference from me. The red-orange beast, however, acts like a red tide and would reduce its hibiscus partner to a tired swimmer trying to keep her nose up to that crimson surface, except that I act as referee.

So I wade into my red-orange poppy every June as the flower petals fall to remove that foliage before its time. I grasp each cluster of poppy leaves and stalks, then give a sharp tug to break it off below soil level. I learned that this does not kill the poppy, just slows its spread. It does free the emerging hibiscus shoots from the poppy’s shade. I can almost hear the hibiscus gulp in air as I pull the poppy out of the way.

Tap root and shallow. The category “tap root” doesn’t always mean a single, straight root but a root that is deep. Hybrid lily, left, has a deeper root than perennial ageratum (Eupatorium coelestinum a.k.a. Conoclinium coelestinum, right), so the two can co-exist harmoniously.
Tap root and shallow. The category “tap root” doesn’t always mean a single, straight root but a root that is deep. Hybrid lily, left, has a deeper root than perennial ageratum (Eupatorium coelestinum a.k.a. Conoclinium coelestinum, right), so the two can co-exist harmoniously.

Accommodate the staggered start.

Some pairings involve plants that are best planted in a certain season—bulbs in fall, the first sowing of a self-seeding annual in spring. Yet you may want to plant their double up counterpart earlier or later. Or you may decide to try doubling up beginning with an established plant in your garden. The challenge is to insert the second plant and insure its good start but cause minimal disturbance to the first.

It can be a puzzle to do this with bulbs, especially the big ones. The plants they double so well with are often in full, glorious bloom at bulb-planting time. Perhaps tiny bulbs can be shoehorned in with a narrow trowel, but the gardener can’t bear to insert a spade and ruin that show. The best answer I’ve found is to wait until November to add the bulbs. Then the new additions still have time to get established before their debut, yet I’m less hesitant to plant in the other plant’s midst.

The reverse of that situation, planting an owl companion in spring among already established larks, is also difficult. Digging to place a one-gallon container of Japanese anemone among bulbs is likely to destroy or at least set the bulbs way back. When working among spring bloomers, it’s more do-able to trowel in several three-inch pots, small divisions of a late riser perennial, or the smallest available cell packs of an annual, or simply sow seeds between the established plants.

Sometimes you do have space at ground level for digging, but the air space is full of stems of established plants. You have to be a terrific lightfoot to avoid bending or snapping stalks as you work in that already tight place. I find elastic tarp straps helpful for cinching in existing plants, temporarily reducing their girth while I plant between them.

Have fun but don’t go broke!

Which brings me to one final, practical aspect of doubling up—the cost. It’s more costly than conventional planting because you plant two for one and there is always the chance that a pairing will fail. That consideration, along with the knowledge that small plugs make better double ups, keeps me always on the look-out for small starts at garden centers and plants that can be divided to plant as double ups. You can also do some begging of perennial divisions from fellow gardeners. Since you’ll request only very small divisions, perhaps your friends will be more likely to say yes. Then you can cut your costs even as you double your perennial show!

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

Filed Under: Janet’s Journal Tagged With: companion planting, Janet Macunovich, Janet’s Journal, perennials

Perennial Partners: Peony and Siberian Iris

May 14, 2015   •   Leave a Comment

Peony ‘Sarah Berhhardt’ and Siberian Iris ‘Caesar’s Brother’
Peony ‘Sarah Berhhardt’ and Siberian Iris ‘Caesar’s Brother’

by George Papadelis

Peony and Siberian Iris are two outstanding perennial partners that complement each other beautifully in both flower and form.  In early May, both plants develop fresh foliage that looks just as handsome in the coldest days of fall. Peonies produce roundish bushes of sturdy, bold, olive-green foliage while Siberian iris yield long, slender, vertical blades of a more bluish green.  This contrast of textures creates a pleasant effect that is too often overlooked when combining plants.  Most gardeners consider flower color, flowering period, and height during the planning stages, but texture is too seldom a concern.

By late May, peonies and Siberian iris have reached their full height of 2 to 3-1/2 feet and both are beginning to bloom. Try the pink peony blossoms of ‘Sarah Bernhardt’ with the violet-blue blooms of Iris siberica ‘Caesar’s Brother.’  For an even showier effect, underplant with the non-flowering lamb’s ears (Stachys ‘Silver Carpet’) or any other silver or white plant. This gorgeous display should last 2 to 3 weeks depending on when the rain disintegrates the peony blossoms.  The use of peony rings or stakes will prolong their effectiveness.  By late June, the flowers have ceased on both the peony and Siberian iris, leaving behind handsome foliage.

Both peonies and Siberian iris are readily available and offer many varieties from which to choose.  They are also long-lived, easy to grow, will tolerate almost any soil, and prefer a full to part sun location.  So, for a showy spring display of color and a season-long contrast of foliage,  try this combination and reap the rewards for years to come.

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

Filed Under: Perennials Tagged With: peony, perennial partners, perennials, siberian iris

Janet’s Journal: Proper Watering

June 1, 2014   •   Leave a Comment

Water is the crux of gardening. For a beautiful garden, spend some time sorting out your plants’ individual water needs and how water flows in your soil.
Water is the crux of gardening. For a beautiful garden, spend some time sorting out your plants’ individual water needs and how water flows in your soil.

Understand your soil and plants roots to help your plants thrive

 

By Janet Macunovich / Photos by Steven Nikkila

The hazy, hot eye of summer is upon the garden. Reach for the hose, but use your head for proper watering.

Herbaceous plants—annuals, perennials, vegetables, etc., that have no wood to hold them up—are simply columns of fluids. Roughly 95 percent water, they stand because liquid pressure holds their cell walls taught. Remove much and they fold. Wilted plants might recover with watering, but damage is done during the wilt: from localized scarring of tissues and greater susceptibility to diseases that can enter through weakened tissue to the more general stunting that occurs because the plant was not able to photosynthesize while dehydrated.

Photosynthesizing is the harnessing of solar energy to make food. Plants use sunlight to split water and carbon dioxide molecules in their leaf cells, then recombine those ions with pinches of mineral matter to make sugars, starches, cell thickeners, new cells and everything else they need. Sunlight is the fuel, but water is the main ingredient, lubricant, coolant and transportation device in these leafy factories. Water’s atoms become part of the product, but water also keeps all parts supple and cool enough to work and is the conveyer belt which brings ingredients together and moves finished products from leaf to stem and root. In brighter light and warmer air, the plant factory works faster and more water is needed to keep it running.

No wonder plants ask for water every time we turn around in summer. The best thing we can do in July is to water wisely, not by rote but using a variety of methods geared to specific plants, soil and weather.

One inch of water per week is the average rule, but all plants are not average. Be aware of your plants’ specific water requirements.
One inch of water per week is the average rule, but all plants are not average. Be aware of your plants’
specific water requirements.

 

Take the standard rule, to give plants one inch of water per week. Some of us set out rain gauges to measure rainfall, then turn on sprinklers as needed to top up to that one inch mark. Others read cumulative precipitation in newspaper weather charts and drag out hoses when rain doesn’t add up. Both are smart practices, better than setting an automatic system to run every day or two, rain or shine. Yet you can water even smarter.

One inch per week is an average, but all plants aren’t average. Some need more because their leaves lose more water to evaporation, or when they’re ripening fruits, or if they were cut back and must fluff out all new foliage. Big, thin leaves may lose so much water through evaporation on a hot, sunny day that the roots can’t keep up even if a hose drips there constantly. As an example, look at a ligularia wilted into a green puddle. Many ligularia plants suffer from root rot in summer too, overwatered by a gardener who reaches for the hose every time the plant wilts. The soil becomes super saturated and airless, so they die of starvation and rot.

Big, thin leaves in the wind and sun may lose so much water so quickly that the roots can’t keep up. Just look at a ligularia spread out on the ground like a green puddle.
Big, thin leaves in the wind and sun may lose so much water so quickly that the roots can’t keep up. Just look at a ligularia spread out on the ground like a green puddle.

 

Some plants need less water than others on a hot or blustery day. Gray, furry or needle-like leaves are designed for minimal water loss. Hairs that make a leaf gray or furry form a layer around the leaf that prevents immediate evaporation or blow-drying of water vapor emerging from pores. The vapor is trapped and sheltered inside the fuzz where it can linger and do its job as a coolant. To grow a gray leaf plant like lamb’s ear (Stachys lanata) next to a wilter like ligularia, water very carefully, feeling for moisture in the soil at the base of each plant before turning the hose on just one plant or the other.

A gray leaf plant such as lamb’s ear (Stachys lanata) does well where it’s hotter and drier. It has a layer of hair on each leaf where water vapor coming out through the pores is trapped and protected.
A gray leaf plant such as lamb’s ear (Stachys lanata) does well where it’s hotter and drier. It has a layer of hair on each leaf where water vapor coming out through the pores is trapped and protected.

The amount of water available to roots isn’t based solely on amount of water poured onto the soil—that inch we measure in a rain gauge or in a wide-mouth container set on the ground under a sprinkler. Whether an inch will mean there’s enough, too little or too much water for the roots varies with type of soil, drainage, air temperature and wind.

Sandy soil has large pores—spaces too big to hold water up against the pull of gravity. Water runs through sand more quickly than through the tiny pores in clay or loam. An inch of water applied all at once to sand may be gone in a day, though in clay it would have lingered at root tips for a week or more. So sand often needs more than an inch of water per week, meted out by the quarter- or half-inch every few days. Sand’s ability to hold water can be improved by topping it with evaporation-suppressing mulch and mixing into it a generous layer of organic matter or pre-moistened water-absorbent polymers (sold as “Water Sorb,” “Soil Moist,” etc.). These materials can absorb and only gradually lose up to 100 times their own weight in water. Yet even fortified this way, a sandy soil will dry more quickly than clay.

Drainage is the movement of water and air through soil pores. Some soils drain quickly, others slowly. Often the drainage depends on the type of soil well below the surface, so even a sand may drain slowly enough that moss grows on its surface. The only sure way to know how long water lingers in a soil, and how soon life-giving air is also back in the soil after a drenching rain, is to dig a hole 3 to 4 inches deep and touch the soil. What feels cool is damp, but aerated. What feels warm or hot is dry. Soil that actually wets the fingertip is still draining.

Doing touch tests can be revelatory.

Even within a city lot with homogenous soil, some spots will dry more quickly than others. South-facing slopes and elevated areas may be dry while soil a few feet away is still moist, since ground tipped to the sun is often warmer and elevated sites catch more breeze and lose more water to evaporation. Dry spots in lawn or garden often show in early spring as dead patches or where one group of plants is slow to emerge.

Bee balm (Monarda didyma) likes a constantly moist soil. If grown on the dry side or where it is very wet and very dry, its chances of developing powdery mildew are greater.
Bee balm (Monarda didyma) likes a constantly moist soil. If grown on the dry side or where it is very wet and very dry, its chances of developing powdery mildew are greater.

 

Lungwort (Pulmonaria species) grown with drought-tolerant bigleaf forget-me-not (Brunnera macrophylla) in the dry shade is more likely to develop mildew than if grown and watered equally with hostas that thrive in constantly moist, well-drained soil.
Lungwort (Pulmonaria species) grown with drought-tolerant bigleaf forget-me-not (Brunnera macrophylla) in the dry shade is more likely to develop mildew than if grown and watered equally with hostas that thrive in constantly moist, well-drained soil.

 

We’re also taught to water gardens less often but more deeply so soil is thoroughly wetted, and probably have been told that watering lightly is bad practice since it “brings roots to the surface.” It’s wrong to think of roots “coming to” anything, but even some of the most scholarly horticultural texts use this phrase that misleads gardeners. As Dr. Joe Vargas of Michigan State University once said in a lecture on watering turfgrass, “I’ve looked at a lot of roots very closely, even dissected them, and one thing I’ve never found is a brain. They don’t know where water is. They can’t sniff it out, either.”

Roots grow if the soil around them is moist enough to supply water and nutrients needed to fuel cell division. They don’t grow if soil around them is too dry. Roots in a dry pocket or dry layer will not move toward moisture.

One thing we learn once we know that roots can’t seek out moisture is that root balls of new plants need special attention. A peat-based root ball of a container-grown plant may dry out far more quickly than the garden loam or clay around it. Roots within the peat will simply stop growing. Until a new transplant’s roots have grown beyond the peat and into the garden soil, its root ball has to be checked separately for dryness even if the soil around it is wet.

Another corollary of “roots can’t go to water” is that although it may be best when sprinkling many flowers, trees and shrubs to water deeply so that the whole depth of the root mass is wetted, plants with shallower roots need frequent, light watering. Lawn roots shorten in summer heat so a daily application of 1/8 inch of water is better than a weekly watering that means days-long drought in the surface layers. Annual impatiens evolved in rich leaf litter in damp jungles, and have shallow roots too. Water them often, but don’t waste water by applying enough to wet the deeper soil layers every time.

Another thing we hear often is that we should water early in the day, not in the evening, so leaves can dry off before night and be less susceptible to disease. This makes sense, reducing the amount of time that fungus-prone leaves are covered in fungus-promoting films of water, but then how does Mother Nature get away with evening and nighttime watering? Thunderstorms and rain showers come when they will, yet the normal state of being for plants in the wild is one of good health—maybe a bit of fungus here and there, but life-threatening epidemics as seen in rose gardens are rare.

If water is applied deeply and occasionally to supplement rain—perhaps weekly or bi-weekly—time of day is not so critical as in an every-day automatic system. Occasional watering means occasional openings for fungus infection. Daily late-day watering increases the chances of fungus infection by a factor of seven or more.

For some plants, an increased chance of fungus infection may be offset by water’s cooling effect. As temperatures rise into the 90s, many plants stop photosynthesizing because their root systems can’t supply enough water to keep that process running at the high speed engendered by high heat. Pores in the leaf close, shutting off the upward flow of water like a drain plug in reverse. Without water flow, photosynthesis can’t take place, and the plant can’t produce fresh sugars to fuel its life processes. It lives off its reserve starches until the air cools. Dr. Vargas’ ground-breaking studies of turf irrigation clearly show that watering during the hottest part of the day is best for lawns because it cools the air around the grass, allowing it to continue to photosynthesize.

Other plants are more susceptible to fungus when exposed to drought or alternating wet and dry. If bee balm (Monarda didyma) that thrives in constantly moist soil is kept dry, its chances of developing powdery mildew are greater. Likewise, lungwort (Pulmonaria species) grown with drought-tolerant bigleaf forget-me-not (Brunnera macrophylla) in the dry shade is more likely to develop mildew than if grown in a constantly moist, well-drained hosta bed.

How about all the hype for weeper hoses and trickle irrigation, to conserve water and keep the leaves from ever getting wet? Does it sound like the only good way to deliver water? With weeper hoses, we often see increased spider mite damage. Regular rinsing keeps mites in check. Roadside plants struggling with pore blockage and light reduction under a layer of grime become more susceptible to pests unless rinsed regularly.

If all this seems too much to keep straight, maybe you haven’t been watered well! Why not go sit in the shade, have a cool drink and think about it? You may see that only one or two of the situations I’ve described here apply to your garden. While the heat’s on and your plants need it the most, fine tune that watering system!

Janet Macunovich is a professional gardener and author of the books “Designing Your Gardens and Landscape” and “Caring for Perennials.” Read more from Janet on her website www.gardenatoz.com.

Filed Under: Janet’s Journal Tagged With: annuals, drought, perennials, photosynthesis, Watering

What perennials are good for using in flower bouquets?

August 14, 2011   •   

What varieties of perennials would be good for using in flower bouquets?

While this list is not all-inclusive, here are some perennials that are well-suited for arranging: Black-eyed Susan (Rudbeckia), Coneflower (Echinacea), Coreopsis (Tickseed), Delphinium, Dianthus (Pinks, carnations), Iris, Lilies, Lavender, Liatris (Gayfeather or blazing star), Peonies, Phlox (tall), Shasta daisy, Sunflower (Heliopsis), Yarrow (Achillea)

Filed Under: Ask MG Tagged With: Coneflower, Coreopsis, Echinacea, flower bouquets, perennials, Rudbeckia, Tickseed

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