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Magnificent Magnolias for Majestic Spring Flowers

Saucer magnolia is one of the most popular magnolias grown and blooms beautifully in early- to mid-spring,

I will always remember the early spring day in the 1960s when I exited the freeway into a wooded neighborhood and first saw saucer magnolia saucer magnolia (Magnolia x soulangeana, 20-25 feet, USDA Hardiness Zones 5-9, a cross between M. denudata x M. liliiflora) in full bloom. It was a spectacular introduction to the genus Magnolia.

Since that day, my interest in magnolias has not diminished and actually continues to grow each spring. In my own garden, I have several and would have more if it were not for space limitations. I regularly visit our local arboretum, the Hoyt Arboretum of Portland, Oregon, in the spring to see the Magnolia collection. There are also several area private gardens with extensive plantings of Magnolias, and I am a regular visitor.

About Magnolias

Saucer magnolias are large, long-lived trees that develop elegant branching with age.

Generally, magnolias are not small trees. Most of them will reach at least 25 feet and many have broad branches. Roger Gossler, of Gossler Farms Nursery in Springfield, Oregon, has an extensive display garden of magnolias, and he told me that he has consistently asked the hybridizers to please breed magnolias that are smaller because many of today’s customers are looking for trees in the 10-15-foot range. (The classic varieties in the Girls magnolia group, bred at the National Arboretum, have many smaller trees with fantastic blooms, but several are no longer on the market, and there is always a need for great new varieties for smaller gardens.)

Magnolia ‘Ann’ is a National Arboretum intro in the Girls series that reaches 10-12 feet tall.

For choosing the best Magnolias for your particular area, check varieties that local garden centers are offering. I also think that one of the best tests for specific varieties is to see what other gardeners are growing where you live. Be sure that they are reliably hardy where you live and not susceptible to early cold snaps in your area, which are known to sometimes freeze the spring buds and flowers.

Most Magnolia’s will grow in a full sun location but many also benefit from some protection from the hot afternoon sun. They like organic-rich and well-drained soil. The addition of Black Gold Garden Compost Blend would be ideal at planting time, and a yearly top-dressing is also beneficial. Magnolia roots tend to be fleshy so transplant them carefully while being sure to lightly tease apart any dense, pot-bound roots.

My Favorite Magnolias

Star magnolias are some of the first flowering trees to bloom with their starry pink or white flowers that appear before the leaves.

There are so many different varieties of Magnolias, and I am only able to list a very small number of them here. As I mentioned earlier, check to see what your neighbors are growing or local garden centers are carrying. It’s a great way to ensure that the trees you plant will grow well in your garden.

Yulan magnolias are fragrant and goblet-shaped.

One of the earliest blooming magnolias, which I have in my garden, is star magnolia (Magnolia stellata, 15-20 feet, USDA Hardiness Zones 4-8). This is one of the smaller growing types, my plant is probably 20 years old and perhaps 10 feet tall. The fragrant white flowers are small, 3 inches across, and appear on the stems before the leaves. The plant is a profuse bloomer and is covered with flowers in late winter.

Another that I have in my garden is Yulan magnolia (M. denudata, 30-40 feet, Zones 6-9), which has fragrant, ivory, goblet-shaped flowers that are 4-6 inches across and open before the leaves appear. Often a few flowers will appear during the summer. A bonus with this tree is that in late summer, red cone-like fruits appear and from a distance look as though the tree is in bloom.

‘Elizabeth’ has unique, pale yellow flowers.

Yellow is a rather elusive color in magnolias and ‘Elizabeth’ (15-30 feet, Zones 5-9) has set the standard since it was introduced and patented by the Brooklyn Botanic Garden in 1977. It has light yellow, fragrant flowers that are 6-7 inches across and often appear before the leaves. Another yellow is M. ‘Butterflies’ which is similar but has smaller, (3-4 inch) flowers.

I would be remiss without mentioning the one that, when in bloom, attracts the most attention in my garden. Magnolia ‘Black Tulip’ (15-20 feet, Zones 5-9) has one of the darkest blooms of all the hybrids. As the name indicates, tulip-shaped flowers that are very dark purple-red appear on stems before the leaves. This makes a spectacular display.

Here I am offering just the tip of the iceberg of available Magnolia selections. I have only mentioned some of those that bloom in early spring, but there are plenty of other varieties that bloom in summer, such as southern magnolias (Magnolia grandiflora) and Virginia magnolia (Magnolia virginiana), so don’t stop with spring!

‘Black Tulip’ is a unique hybrid with very dark, tulip-shaped flowers.

Why Won’t My Dahlias Bloom?

Why Won’t My Dahlias Bloom?

“I have tried everything to grow Dahlias. They come up sometimes to about 1ft and never bloom.” Question from April of Dresden, Tennessee

Answer: I am sorry to hear that you are having trouble with your dahlias flowering. There are several factors that impact dahlia blooming, including light levels, fertilizer, and dahlia type. First, provide them with full sun–eight or more hours per day is best. Feed your plants with a quality fertilizer formulated to encourage flowering to boost blooms. Finally, choose more compact dahlias with a free-flowering nature. Try varieties in the Gallery Series, which are more compact and flower nonstop. Dahlias in the Happy series are also outstanding when it comes to repeat bloom. Happy Single Flame is especially pretty with its hot pink and yellow single blooms. For more information, I encourage you to read the following blog and watch our video about growing Dahlias to perfection. (Click here to read All About Growing Dahlias.)

Happy Dahlia growing!

Jessie Keith

Black Gold Horticulturist

 

 

 

 

 

 

 

 

 

 

Why Did My Iris Take So Long to Bloom?

Why Did My Iris Take So Long to Bloom?

“Why Did My Iris Take So Long to Bloom? I planted Irises about three years ago & this is the first year they have bloomed. Is that normal?” Question from Rosie of Wichita, Kansas

Answer: I am going to assume you are growing German bearded iris (Iris germanica), the most common iris variety in the United States. There are lots of factors that may have caused yours to be late in blooming, such as small starting size or less-than-ideal growing conditions. Since I am not certain of your plant’s garden conditions, let me simply share what German iris need to thrive.

These popular garden flowers perform best when given full sun and fertile, well-drained soil conditions. (I recommend adding Black Gold Garden Compost Blend if your soil is low in organic matter.) Bearded iris rhizomes should be planted with the tops at or slightly above the soil surface, as those planted too deeply may result in lush foliage but fewer or no flowers. Late spring freezes, which can halt early stem and bud development after the plant has sprouted, are another common cause for lack of flowering in bearded irises. Other factors that might have impacted the delay in blooming are lack of sufficient sunlight, poorly drained soil, or insufficient soil nutrition.

I hope that these insights help. And, if you think there are some improvements that can be made to the growing conditions of your iris, I encourage you to make them. It is always wonderful when iris are in full bloom in spring.

Happy gardening,

Jessie Keith

Black Gold Horticulturist.

Why Isn’t My Hydrangea Flowering?

“I have hydrangeas but each year they only get leaves and no flowers what can I do?” Question from Nancy of Campbell, Ohio

Answer: Generally when gardeners have trouble with hydrangeas that refuse to bloom, they are largeleaf hydrangeas (Hydrangea macrophylla hybrids). These survive just up to USDA Hardiness Zone 5, your zone, but you should be able to get them to bloom.

Largeleaf hydrangeas bloom on “old” or last year’s stems, so it is important not to prune them back in spring or fall. If trimming is needed, they should only be pruned right after they flower in summer. On occasion, harsh winters will cause stem dieback–killing all of the flowering stems down to the ground. Deer can also nibble them. When this happens, expect few to no flowers that year.  (Click here for an excellent schematic by Proven Winners that visually explains why some hydrangeas won’t bloom.)

Another factor is that largeleaf hydrangeas bloom best in partial sun. If yours is in deep shade, consider moving it. In your zone, the best garden spot for a largeleaf hydrangea is a partially sunny, protected location. Planting it near a building or wall will give it some protection from the harshest winter weather.

If you don’t feel like bothering with all of these steps, we recommend planting smooth hydrangea (Hydrangea arborescens) varieties, which are very hardy and bloom on new wood. Two really exceptional types are Incrediball® and Invincibelle® Ruby. These grow best in fertile soil and like the addition of fertilizer formulated for flowering shrubs. I recommend amending their planting hole with Black Gold Garden Soil, which feeds plants for up to six months.

I hope that these tips help!

Happy hydrangea growing,

Jessie Keith

Black Gold Horticulturist

Shrubs with Fall Color

This late-season Pacific Northwest landscape shows the bountiful blooms of a pink-flowered crape myrtle.

In the spring, gardens come alive with tulips and other spring-flowering bulbs, and the peonies and many other herbaceous perennials emerge from the soil.  It is a time of much BG-Peat-Moss-8qtanticipation for gardeners.  We often visit our local garden centers to see what is new, in bloom, and what we must have. In the fall season, however, gardeners are less apt to visit garden centers or other gardens. As a result, many late-blooming trees and shrubs are overlooked when there are so many trees and shrubs with fall color to consider.

I began to seek out trees and shrubs that provide good fall color some time ago. Whether the color comes from flowers, berries, bark, or foliage, there is a surprising assortment to chose from. My plants of choice were selected for Pacific Northwest gardeners, but they can also be cultivated in other parts of the country.

Hydrangea

Hydrangea quercifolia fall color JaKMPM
Hydrangea quercifolia fall color. (Photo by Jessie Keith)

While hydrangeas are noted for their spectacular flowers in late spring and summer, some varieties provide great fall color.  One is Hydrangea paniculata ‘Fire and Ice’.  The cream-colored spring flowers change to pink as the season progresses, and by the end of summer the papery blooms turn dark to medium pink.

Oakleaf hydrangeas (Hydrangea quercifolia) put on a great fall show with both colorful flowers and foliage. Not only do their pinkish-tan flowers remain attractive into winter, but their leaves turn brilliant shades of red. ‘Snow Queen’ is a large, carefree oakleaf hydrangea with rich mahogany red fall leaves and very large flowers.

Hydrangeas grow best in humus-rich, moderately moist soil.  Before planting amend with Black Gold Peat Moss Plus. It contains an organic wetting agent and helps hold soil moisture during the hot days of summer.

Crape Myrtle

There are so many selections of crape myrtle (Lagerstroemia indica) that it can be difficult to make a decision if one only has space for a single plant.  Older varieties were traditionally late blooming and prone to powdery mildew here in the Pacific Northwest, but most new selections are resistant to powdery mildew and will flower from July to September.  An added bonus is that crape myrtles bloom on new growth, so they can be pruned to size in winter or spring if space is a consideration.  The flower colors range from white to lavender to shades of pink and red.  Some varieties even have red, bronze, or dark purple foliage, which can provide a nice contrast against a home or large border.

Peanut Butter Shrub

Clerodendron trichotomum fruits look almost like flowers and remain colorful on the shrubs until early fall.
Clerodendron trichotomum fruits look almost like flowers and remain colorful on the shrubs until early fall.

Clerodendron trichotomum, often referred to as the “peanut butter shrub” due to its leaf and stem fragrance, is a mid- to late-summer bloomer that produces brilliant clusters of fall fruits.  Each fruit has four fuchsia calyces that surround a metallic turquoise drupe. The showy fruits remain on the tree into the early fall.

European Spindle Tree

Euonymus europaeus 'Aldenhamensis'
Euonymus europaeus ‘Aldenhamensis’ has cheerful pink and orange fruits.

Euonymus europaeus ‘Aldenhamensis’, (European spindle tree) produces a comparable display of brilliant fruits.  In spring, rather nondescript clusters of small white flowers appear. In fall, fruits appear that are brilliant pink outside and open to show orange berries.  If that is not enough, the leaves turn brilliant fuchsia before dropping.

There is much to be seen in the garden at this time of year.  Not only are summer annuals still going strong and dahlias at their prime, but many trees and shrubs are putting on quite a show that should not be missed.  It is a good time to visit your local garden center to discover these and other fall-blooming trees and shrubs for autumn. (Click here to discover more fabulous fall-blooming shrubs.)