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Plant summer-flowering bulbs in early spring

April 4, 2024 • Leave a Comment

If you want to enjoy summer-flowering bulbs in your garden, you may be disappointed if you wait until all danger of frost has passed before planting these beauties. Flowers may come late in the fall and be missed. Consider an early start (roughly mid March to mid April) for larger cannas, large-flowering dahlias, elephant ears, and anything else you want to have in flower earlier than late summer.

Materials needed to get bulbs started: 6- or 8-inch pots, lightweight planting soil, bulbs, and plant labels. Read the planting directions on each bulb package. If you saved bulbs from last year’s garden, plant them in the pots so that they are just completely covered, roots down. Don’t plant them too deep. It’s better to err on the side of too shallow.

Once the bulbs are planted, thoroughly water them. This will help signal to the dormant bulb that it is time to spring to life. At this stage, the pots don’t need any light. They need warmth and water. So leave them in the basement or out of the way.

When new growth begins emerging, watch carefully. Treat them like houseplants when it comes to watering, allowing them to dry out a little between waterings. Every couple weeks, apply a water-soluble fertilizer. When the first leaves are beginning to separate from the shoot, move the plants to a bright, but indirectly lit window. It should take about two weeks from potting time until the plants are moved to the window.

These plants shouldn’t be planted into the garden until all danger of frost has passed. But they can still get some quality time outdoors. The bulbs can visit outside if the temperatures don’t drop below 50. Never expose them to frost! Overnight exposure is out of the question, unless it is in the garage, and the temperature will not drop below 45. It’s best to wait until early May for any overnight trips.

Continue to fertilize and expose plants to the outdoors. When the weather allows, usually mid to late May, transplant them into the garden. Stake the plants if necessary, being careful not to damage the bulb. Remember, do not allow the plants to be exposed to frost, or all of your hard work will be undone. If frost is predicted, cover the plants with rose cones or frost guard fabric.

Follow these steps and you will enjoy beautiful summer flowers!

Provided by the professionals at English Gardens.

ELSEWHERE: Storing tender, summer-flowering bulbs, corms, rhizomes and tubers for winter

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.

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Hellebore

Phenological indicators