Shrubs 101

As I’ve gotten older…no, let’s make that…as I’ve gained gardening experience, the more I’ve come to appreciate the value of good foliage plants in the garden. But in spite of that, I freely admit to being a sucker for spectacular floral displays. And flowering shrubs undoubtedly qualify as plants that have the ability to knock your socks off with their flower shows.

In addition to their beauty, flowering shrubs give much needed structure to gardens. They provide a vertical backdrop for other perennials and serve as a transition layer from trees to smaller plants. They work equally well as specimens, in groups or as hedges.

Plant them in spring or fall and though most prefer full sun, there are several that will thrive in part shade. Be sure to read the cultural instructions before planting. Shrubs are easy to grow and they will provide years of beauty in your landscape.

Now I’m going to share a secret with you. Even though neglected shrubs will flower, if you want loads of beautiful blooms from your shrubs, you have to be willing to do a hack job on them. That's right. In gardening lingo we call it pruning and it is the key to abundant flowering. As a general rule, flowering shrubs should be pruned immediately after flowers are spent; never before. Pruning at the wrong time is actually worse than not pruning at all. Take out the oldest and largest stems first. Prune back about 1/3 of those stems. Don’t be afraid to be aggressive and you will be rewarded the following spring for your efforts.

To me, nothing proclaims spring quite like the intoxicating scent of a lilac in full bloom. When I catch a whiff of their heady aroma, I am immediately transported back to childhood. Lilacs are an old fashioned favorite that never go out of style. They are hardy, easy to grow and in my opinion, still one of the nicest flowering shrubs. They average six to eight feet in height and come in a variety of colors from the many shades of purple, pink and red to white and even yellow. Dead-heading, or cutting off faded flower heads, is another secret that improves next season’s flowers. Lilacs can be prone to powdery mildew so they need good air circulation around them. One of my current favorites is ‘Josee,’ which will re-bloom if regularly dead-headed.

Forsythias are one of the first shrubs to flower in the spring. Their cheery yellow flowers join those of the daffodils in welcoming spring. And if you can’t wait for them to bloom outside you can cut dormant branches to force indoors for early flowers. Forsythias are very fast growing and will bloom best in full sun. Remember the secret about pruning I shared with you? It’s particularly important with forsythias as their flowers form only on last year’s growth. A couple of good varieties for us are ‘Sunrise,’ which is an Iowa State University introduction and ‘Meadowlark.’

Because of our climate, we’ve always been severely limited on the varieties of hydrangeas we can grow here. Until the last few years, only the old standard, ‘Annabelle’ really thrived. And though we still can’t grow many of the classic macrophyla, or mophead hydrangeas, we have some exciting new options. ‘Endless Summer’ is a big departure in appearance from ‘Annabelle.’ It is a breakthrough for cold-climate gardeners because it flowers on the current year’s growth as well as on old wood. This means that killing frosts are no longer an issue. I’ve had reliable flowers on mine even though we’ve had late frosts the last couple of years that caused dieback. ‘Limelight’ is a paniculata variety of hydrangea that blooms a lime green and fades to pink. It is fully hardy here. There are also several varieties of oak leaf hydrangeas, including my favorite, ‘Snow Queen.’

Well, there are way too many flowering shrubs for one post. Looks like I’ll have to carry this topic into my next post. In the meantime, check out an old favorite gardening show which has recently returned to HGTV, ‘Gardener’s Diary.' Check your local listing for broadcast times. Host Erica Glasener takes you around the country in search of inspirational gardens and gardeners. Maybe it will inspire your garden creativity.

Going Out on a Limb

I’m going to ask you to get up from your computer and walk out your front door . Now cross the street, turn around and look back at your house. Take a good look at the landscaping. Does your eye flow smoothly across the yard or do you see obvious gaps? Is there one spot that seems to cry out for a vertical focal point? Now go look at your backyard. Can you picture a small ornamental tree over in the corner by the fence or maybe where the swing set used to be?

Trees are always the best place to start when landscaping and the value of ornamental trees cannot be overstated. In addition to beauty, they provide vertical interest, shade and scale for other plantings. Early spring and fall, when the trees are dormant, is the ideal time to plant

There are several useful ornamentals for us Zone 4 gardeners, but I’m going to focus on a couple of the best ones.

It’s difficult to find fault with the Flowering Crabapple (Malus). It is the most popular ornamental tree in northern climates for good reason. Few ornamental trees offer such an extensive variety in size, shape and flower color and they score high marks for multi-season interest. With over 35 species and several hundred cultivars, you are guaranteed to find one that suits your needs.

Crabapples can be columnar, rounded, horizontal, weeping, pyramidal or vase-shaped. They may have pink, white or red flowers. Foliage color is usually medium or dark green, but it can also be bronze and almost all crabapples have attractive fall foliage. Ornamental fruit that attracts birds appears in the fall and, in some cases, persists through the winter.

Most flowering crabs bloom before the leaves unfold and have darker buds that open to lighter flowers. They average between 15’ - 25’ and like full sun and well-drained soil. One of the best things about them is that they are highly adaptable to many environments. What more could you ask?

Once you determine what shape and color of Flowering Crabapple you’d like to plant, check out the local nurseries to see what they recommend or take a look at a couple of my choices. 'Prairie Fire,’ is a rounded dark pink variety that is definitely a winner here and is my personal favorite. A useful white flowering variety is ‘Sargent,’ and a nice upright light pink crabapple is 'Pink Spires.'

The Eastern Redbud (Cercis Canadensis) in bloom is an unmistakable sign of spring in our area. The lavender-pink blooms, large heart-shaped leaves and the interesting structure of the tree make it very appealing. It does well in full sun or part shade and it thrives in most soil types. I’ve always found it striking as an understory tree on the edge of wooded areas. It grows to around 15’ - 20’ feet with a similar width. The redbud is a good choice for dry areas as it is very drought tolerant.


I’m secretly yearning for the white version, ‘Alba’, of the Eastern Redbud and yes, I know that makes the name a bit of a contradiction.

One of the newest redbud cultivars is ‘Lavender Twist’, aka ‘Covey’. It is a lovely weeping version with zigzagging branches that will grow to a maximum of 8’. It makes a wonderful specimen in the garden and although it claims to be a new cultivar, I’ve had this tree for about three years now. It is truly eye-catching.

A few other ornamental tree options you may want to investigate are Magnolias, Dogwoods and Ornamental Pears. If you have a sheltered spot and are patient and willing to fuss a bit, Japanese Maples can easily become an addiction.

Whatever your choice, every landscape can benefit from ornamental trees. One final comment. Remember to locate all underground utility lines before you dig. The power company and your neighbors will thank you.

I Know It's Spring Somewhere!

Confession time. How many of you die-hard ‘four seasons’ lovers will admit to having had lustful dreams of warmer climates along about mid-February? Come on. Raise your hands. No one will judge you. The truth is that after a winter like the one we’ve all just been through here in central Iowa only those hardiest of souls, the dreaded winter-sports fiends among us, would be sad to see the end of the cold and snow.

One of the best things about a winter like this one is that it makes you appreciate spring that much more. And for those of us who enjoy gardening, the arrival of spring means that we are finally able to do what we’ve been chomping at the bit all winter long to do. We can grab our spades and do some digging in the dirt. But what’s the point of digging if we can’t find something new and interesting to put in the ground?

So to that end, on a dark, dreary day in January I began perusing my newly arrived garden catalogs and checking out the online nurseries to see what new and exciting plants the breeders have for us this year. I found several gems among the 2008 introductions.

For me, one of the most exciting breakthroughs of the last few years has been the outstanding new varieties of coneflowers that have become available. Coneflowers, or Echinacea, thrive in our area and provide very useful structure and color in the garden. A future column will be devoted entirely to these beauties but there are a couple of new cultivars worth mentioning here.

The first is Echinacea 'All That Jazz'. This lavender pink variety gives coneflowers a whole new look with quill shaped petals resembling spoons that will act as magnets for hummingbirds and butterflies. It has a very nice bushy habit and maintains the vigor of traditional coneflowers.

Another new Echinacea is ‘Tiki Torch’. Introduced by the Terra Nova nurseries of Oregon, ‘Tiki Torch’ boasts bold orange blooms that hold their color well. The flowers are long lasting, have a slight spicy fragrance and they make excellent cut flowers.

As with all coneflowers, both of these varieties do best in full sun and well drained soil.

Monrovia Nurseries are offering three new cold-hardy Hibiscus moscheutos. All are hardy to zone 4 and prefer full sun and fertile to average soil. The first of the three is ‘Dave Fleming’. This one has ruby red flowers and maroon tinged foliage. The next is ‘Strawberries and Cream’ which has a bi-color flower of hot pink fading to pale pink. The last is the lipstick-pink ‘Stardust’ which has soft green foliage accented with purple.

A new bee balm, Monarda Bergamo, is the 2008 Fleuroselect Gold Medal Winner. Bee balm is a staple in mid-Iowa gardens and this annual version claims to be mildew-free, which is a big deal here. The drawback is that it is an annual. Still, beggars can’t be choosers and it is supposed to flower in only 8 – 10 weeks from seed. This new Dutch introduction has rose-violet, season-long blooms that are highlighted by its light green foliage.

And, who doesn’t love a good petunia? A few years back, Wave petunias burst onto the gardening scene and took this very adaptable and useful annual to a whole new level. There have been several new introductions in the last couple of years including ‘Tidal Wave’ and ‘Double Wave.’ This year, say hello to ‘Shock Wave.’ This improved strain has all the advantages of the original Wave petunia, but with smaller, 2” flowers and a more mounded habit.

So, there you have it. A few new plant ideas that should make even the most ardent snow bunnies long for spring. Now run, don’t walk, to your nearest garden center, or pick up a new garden catalog or check out the online nurseries to see what you can find. I’ve only just scratched the surface. Get out there and dig!