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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.

We will continue to update our Website with articles and enter current gardening events in our website Event Calendar. All the best wishes for 2024 and beyond.

Hellebores are an early spring superstar bloomer

March 22, 2024 • Leave a Comment

Lenten rose and Christmas rose are common names for hellebores (Helleborus), a gardener’s gift in the dreariest weeks before the spring planting season. In a “normal” Michigan winter, hellebores will begin flowering in March and last through May, thus generating 8 to 12 weeks of showy blossoms. Although many interesting species exist, this article will concentrate on the larger, brighter-colored blossoms of hybrids developed from the Lenten rose (Helleborus orientalis).

Despite the winter, hellebores will explode into bloom at the slightest hint of spring, with blossoms 10 to 18 inches high, above thick stems. Established plants produce multitudes of large, single flowers that shine with grace and beauty, concealing their durability. Colors range from pure white to yellows, greens, pinks, plums, rose, and the darkest purple. Petals may have a variety of shading, veining, and spotting that is rarely seen in garden flowers.

Hellebore Royal Heritage series — **Royal Heritage series (Photo: Wayside Gardens)**

Shortly after blooming, hellebores develop fresh foliage 16 to 22 inches tall and wide. It ranges from the finely cut leaves of certain species to the large, bold leaves of the more common orientalis hybrids. Leaf color ranges from pale to dark green and may be mottled with silvers, grays, and pinks. Hellebores are semi-evergreen in our climate—that means that the foliage may remain undamaged and green in the mildest of winters, while severe winters may discolor and flatten stems and leaves.

Despite their very early performance, hellebores are perfect companions to a number of spring bloomers. They combine well with the earliest-blooming bulbs such as crocus, scilla, or anemones. Fall-planted pansies and violas often produce flowers very early when hellebores are in full glory.

**Hellebores are one of the first perennials to bloom in early spring. (Photo: Eric Hofley / Michigan Gardener)**

The earliest-blooming perennials such as primrose (Primula), lungworts (Pulmonaria), barrenwort (Epimedium), and some woodland wildflowers like trillium are also good hellebore partners. The glossy, bold, dark green foliage of Lenten rose hybrids persists through the growing season and contrasts beautifully with gold, silver, and bright green leaves. Try the gold leaves of certain hostas, golden creeping Jenny, or hay-scented ferns. For an equally stunning combination, position hellebores next to the silver foliage of lamium, Japanese painted ferns, silver-leaved perennial forget-me-nots (Brunnera macrophylla ‘Jack Frost’ or ‘Sea Heart’), or some lungworts such as ‘Moonshine’ or ‘Majesty.’

Hellebores will survive in sun or shade, but the foliage might look fresher if protected from the summer’s midday sun. Our Michigan clay soil is usually alkaline, which is fine for hellebores, but the poor drainage typically associated with clay should be corrected by adding pine bark or compost.

**Breeders are creating hellebores with gorgeous flowers. (Photo: Eric Hofley / Michigan Gardener)**

Hellebores have few pest and disease problems, but black spot is the most damaging and widespread difficulty with which hellebores must cope. Black or brown blotches may appear on leaves and spread to discolor flowers. Overhead watering, a lack of air circulation, and wet weather may contribute to infection, especially when plants lack proper cultural conditions. Removing the spent flowers and infected leaves will help minimize the spread of the black spot spores. Fungicides may also be used.

Lenten rose hybrids were initially available in mixtures that included many possible colors. These mixtures provided many beautiful, rich flowers, but also included several bland and less desirable forms. The safest way to buy hellebores was to purchase them when they were in bloom to ensure the best selections. Then, the “Royal Heritage” strain was developed, which offers larger flowers and an improved brilliant color range.

**Hellebore foliage can be a lovely, dense groundcover. (Photo: Eric Hofley / Michigan Gardener)**

Today, several varieties are available that offer specific colors or forms. The Royal Heritage strain has several varieties that each provide specific colors. Recent series include Frostkiss, Gold Collection, Honeymoon, Wedding Party, Winter Angels, Winter Jewels, and Winter Thrillers. With series like these, hellebores can now be purchased out of bloom, knowing that you will get the color you want.

Fresh hellebore flowers can be cut with a little stem remaining and floated on water for a breathtaking indoor display—these flowers are ideal for being appreciated up close. Blooms can even be dried as an everlasting flower.

In general, hellebores are underused. They bloom so early that gardeners are often visiting the garden center well after they have flowered. Plant one for an early reminder each season that spring is right around the corner. Plant a few and enjoy drifts of pristine flowers that you’ll look forward to year after year.

Hellebore

Common name: Lenten rose, hellebore (HEL-eh-bore)
Botanical name: Helleborus orientalis (or Helleborus x hybridus)
Plant type: Perennial
Plant size: Height and width: 16-22 inches
Habit: Clumping
Hardiness: Zone 4
Flower color: White, yellows, greens, pinks, plums, rose, dark purple
Flower size: 2-3 inches wide
Bloom period: Late winter to spring (March to May)
Leaf color: Glossy, dark green
Leaf size: Up to 16 inches long, rising from base
Light: Partial shade to shade. Avoid afternoon sun.
Soil: Well-drained
Uses: One of the earliest plants to bloom; use it to welcome the spring season.
Companion plants: Bulbs: crocus, scilla, anemones. Fall-planted pansies and violas. Early-blooming perennials: primrose, lungworts, barrenwort, trillium.

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

Phenology: Use nature’s calendar to improve your garden

March 8, 2024 • Leave a Comment

Spring is coming! How can you tell? Don’t glance at the calendar—look at the plants around you. Since they useheat from the sun to become active, plants and bugs are better than the weather forecasters. They are like little solar panels that absorb heat. When they get enough, they begin to develop and change according to how much they have absorbed.

Scientists use a system that is based on days that the temperature reaches 50 and above to calculate this activity—they call it DD50 (Degree Day of 50 degrees). Most insects and plants need a temperature of at least 50 degrees to start to become active. The hotter it gets, the quicker they change. 50 is used as a base degree day, so for each degree above 50 the temperature rises, so does the DD50. For example, a 70-degree day would have a DD50 of 20.

Entomologists have charted insects according to how many cumulative DD50s it takes for them to become active and develop into different life stages (egg, nymph, larva, and adult). For instance, it takes the birch leaf miner adult an average DD50 of 180 to emerge and start laying eggs in the tissue of birch leaves, while the larva needs 262 DD50s to become active.

By using this information, we can better track and control undesirable insects by applying treatments when they are the most vulnerable—usually when they are in the nymph stage, just after egg hatch. Many insects become active between 100 and 200 DD50—that is usually the end of April to the beginning of May. But how do we tell when? Most of us are too busy to sit down and do the math, and every landscape is different. You might have several different DD50s in one yard, depending on microclimates and exposure to the sun.

Phenological indicators

The solution is simple. We use phenological indicators to tell us when a certain DD50 has been reached in an area. These are signals that nature gives us in the landscape. Since both plants and insects need a certain DD50 to become active, we can match them together to tell when an insect is active, based on which flowers are in bloom or when a plant leafs out. There are thousands of these indicators out there and they are pretty easy to learn once you know what to look for.

A common one is the lilac. When it blooms, the birch leaf miner is beginning to lay its eggs in the leaf tissue of birch. So when you see the lilac flowers, you need to check your birch for signs of infestation and treat if necessary.

There are many phenological indicator lists available from your county extension service and various gardening sources, or you can make your own. The next time you see a problem insect in your garden, look around and see what plant is coming into bloom or going through any other noticeable change—then make note of it. Next year, when you see the plant going through the same change, you will know that it is time to check for those same insects in your garden. These indicators are very accurate and do not change from year to year, only the date will vary,depending on the weather.

The tracking of phenological indicators is considered an accurate gauge to our changing climate. Scientists and volunteers all over the globe are recording them to help understand how our world is transforming due to climate change. In Europe, there is a huge network that tracks the first leaf, full leaf, and first bloom of many plants. In some areas they have data going back hundreds of years.

In the U.S., there is a group called The USA National Phenology Network that tracks a multitude of species (www.usanpn.org) and publishes the data every year.Volunteers can report to the site; the information you need is online. Scientists use this data to help predict changes in weather patterns and the effect they have on different plants and insects. This also impacts other animal environments, such as bird migrations and fish spawning.

These indicators are all linked together and can help explain why certain plants no longer grow in areas where they once flourished. It also explains why some springflowers reemerge in the fall—a late season cold snap sends the plant into dormancy and effectively “resets” its DD50. Then a warm fall accumulates enough DD50s to force the plant into growth.

By increasing our knowledge in this area, we begin to see the whole picture of our environment a little clearer. As a result, we can respond more effectively to the signs that nature gives us.

April and May are great months to try out your observation skills and find some good indicators in your own yard. Have fun!

Steve Turner, Certified Arborist, is from Arboricultural Services in Fenton, MI.

Growing roses in your “up north” garden

February 15, 2024 • Leave a Comment

One of the most time-honored Michigan traditions is traveling “up north” to spend idyllic weeks in the sunshine, water and woods. Some of us have cottages or second homes up north. While we don’t want to turn a cottage into just another suburban home, many cottage dwellers like to plant a few ornamental plants to enjoy flowers. Often, roses are rejected as being too fussy for up north. Nothing could be further from the truth.

The growing conditions up north are indeed different than a typical suburban garden. The most obvious difference is the weather. That’s a big reason we trek up north—it’s cooler, both in the summer and in the winter. Those winter lows can create challenges for roses. Up north gardens often contend with much more wind than in suburbia, especially if the cottage sports a lakefront vista. The sandy soil up north is inviting to clay-challenged suburban gardeners because it is easier to dig. However, that same soil doesn’t hold water or nutrients as well as the familiar subdivision clay soil.

Further, cottage dwellers aren’t able to provide their up north gardens with consistent care. Cottages often are empty for days or even weeks during the growing season, while residents earn their living in the big city. That means that plants aren’t watered regularly and there’s little time for spraying pesticides. Besides, who wants to apply toxic chemicals in the natural, up north environment? Seasonal cottages are often shut down in late September. The dock is pulled from the lake and the plumbing is drained and turned off. That’s a little too early to winter-protect tender roses, yet it may be the last time the owners visit the cottage before spring.

Even with all these challenges, roses can thrive up north with just a few special “tricks.”

Select winter-hardy roses and plant them in a sunny spot

This simple advice goes a long way in guaranteeing success with up north roses. There’s no getting around it: roses are sun lovers—the more sun the better. Roses convert sunlight to energy and energized roses are better able to survive winter chill, drought and pests. Plant a winter-hardy rose in a sunny spot and you’ll be rewarded with decades of bloom, even up north.

Some of my favorite up north roses include the hardy, fragrant rugosas and Canadian-bred Explorer and Morden Parkland roses. If you’d like a rose for cutting, consider the many bred by Dr. Griffith Buck at Iowa State University, known fondly as “Buck” roses. His pink and red roses are the most winter-hardy, while the white, yellow and apricot ones may need some extra winter mulch to survive up north.

Don’t overlook the once-a-year-blooming antique roses. They will create 3 to 4 weeks of show in mid-to-late June up north—exactly the time you will be visiting your cottage. After blooming, these hardy survivors turn into leafy, rounded shrubs, at home in a naturalistic setting. They’re reliably winter hardy and rarely bothered by insects and diseases. They’re survivors—that’s how they’ve lived to become antique roses! Several ancient rose varieties are native to Michigan, including prairie rose (Rosa setigera) and swamp rose (Rosa palustris).

This simple advice goes a long way in guaranteeing success with up north roses. There’s no getting around it: roses are sun lovers—the more sun the better. Roses convert sunlight to energy and energized roses are better able to survive winter chill, drought and pests.

Plant when you’re going to be at the cottage for a few weeks

Spend some time working organic amendments into the planting area. Put about 1/2 cup of bone meal at the bottom of the planting hole. This provides a good, very slow-release form of phosphorous, essential for root development.

Water heavily while planting and water newly-planted roses every day for several weeks; ideally a month. Water is the best “miracle chemical” to ensure success for a newly planted rose. It’s OK to use lake water on roses and may be better than mineral-rich well water. After a few weeks, reduce the frequency of watering, but plan to supplement nature’s rainfall during the first year, when roses need water 2 or 3 times weekly, especially in sandy soil. After the first year, roses are better able to withstand periods of drought.

Hold off fertilizing a newly planted rose for about a month. Check new roses frequently for animal damage. Critters seem to be attracted to freshly worked soil and could uproot your roses looking for the bone meal or tender roots to munch.

Once the roses are established, there are two treats that will bring them from so-so to spectacular: slow-release fertilizer and organic mulch.

Apply slow-release fertilizer in late spring or early summer

The plastic-coated, slow-release fertilizer pellets release nutrients slowly over 3 or 4 months. Roses are heavy feeders and, unfortunately, sandy soil doesn’t hold nutrients well. Organic fertilizers are good as well, but in sandy soils they must be used monthly from May through August. Compost is a good organic soil amendment that improves soil structure, but it doesn’t provide enough nutrients when used as the only fertilizer.

Several inches of organic mulch corrects many problems

Shredded pine bark mulch is readily available up north and is a wonderful top-dressing around your roses. It helps moderate soil temperature and moisture level, making your roses more forgiving if you must ignore them for weeks at a time. It smothers weeds and makes it easier to pull them. Over time, bark mulch decomposes, adding much needed organic matter to sandy soil. Spread a couple inches each year to replace the mulch that’s decomposed into the soil and to dress up your garden with a fresh look.

Heap some extra mulch around the crown for the first winter

Even the very winter-hardy varieties mentioned in this article aren’t fully established for their first winter. Their roots could frost heave and the tender new canes could attract rabbits. Heap 6 to 10 inches of extra mulch around the crown for the first winter. Hardy roses won’t need any special winter mulch in subsequent years, but you may need to ring them with mesh wire if the critters enjoy your winter garden.

Give your up north roses a little extra attention each May

Wait until the rose starts to leaf out, and then pull away leaf debris around the plant to create a little basin that helps collect water around the crown. Prune off any winter-damaged canes and shape the shrub, even if it means pruning some portions that are already pushing leaves. Apply slow-release fertilizer around the drip line of the plant and scratch it into the soil or mulch. You don’t have to bury the fertilizer, just get it in contact with the soil. Spread a couple inches of fresh organic mulch and water the plant very thoroughly to get the fertilizer’s nutrients to the roots. That’s it. Now enjoy hundreds of blooms from your lake-side hammock all summer!

Nancy Lindley was the co-owner of Great Lakes Roses in Belleville, MI.

ELSEWHERE: Why are my roses changing color?

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